The Biblical concept of “preaching” is best ascertained from an examination of the sense of the original Hebrew and Greek terms. The Greek ke·rysʹso, which is commonly rendered “preach,” means, basically, ‘make proclamation as a herald, to be a herald, officiate as herald, proclaim (as conqueror).’ The related noun is keʹryx and means ‘herald, public messenger, envoy, crier (who made proclamation and kept order in assemblies, etc.).’ Another related noun is keʹryg·ma, which means ‘that which is cried by a herald, proclamation, announcement (of victory in games), mandate, summons.’ (A Greek-English Lexicon, by H. Liddell and R. Scott, revised by H. Jones, Oxford, 1968, p. 949) Ke·rysʹso thus does not convey the thought of the delivery of a sermon to a closed group of disciples but, rather, of an open, public proclamation. This is illustrated by its use to describe the “strong angel proclaiming [ke·rysʹson·ta] with a loud voice: ‘Who is worthy to open the scroll and loose its seals?’”​—Re 5:2; compare also Mt 10:27.

The word eu·ag·ge·liʹzo·mai means “declare good news.” (Mt 11:5) Related words are di·ag·gelʹlo, “declare abroad; give notice” (Lu 9:60; Ac 21:26; Ro 9:17) and ka·tag·gelʹlo, “publish; talk about; proclaim; publicize.” (Ac 13:5; Ro 1:8; 1Co 11:26; Col 1:28) The principal difference between ke·rysʹso and eu·ag·ge·liʹzo·mai is that the former stresses the manner of the proclamation, that it is a public, authorized pronouncement, and the latter stresses the content thereof, the declaring or bringing of the eu·ag·geʹli·on, the good news or gospel.

Ke·rysʹso corresponds in some measure to the Hebrew ba·sarʹ, meaning “bear news; announce; act as a news bearer.” (1Sa 4:17; 2Sa 1:20; 1Ch 16:23) Ba·sarʹ, however, does not imply official capacity to the same extent.

Preaching in the Hebrew Scriptures. Noah is the first person designated as “a preacher” (2Pe 2:5), although Enoch’s earlier prophesying may have been made known by preaching. (Jude 14, 15) Noah’s preaching righteousness prior to the Flood evidently included a call for repentance and a warning of coming destruction, as is evidenced by Jesus’ reference to the people’s ‘failing to take note.’ (Mt 24:38, 39) Noah’s divinely authorized public proclamation, therefore, was not primarily a bringing of good news.

Following the Flood, many men, such as Abraham, served as prophets, speaking forth divine revelations. (Ps 105:9, 13-15) However, prior to the establishing of Israel in the Promised Land, regular or vocational preaching does not seem to have been done in a public way. The early patriarchs were under no instructions to act as heralds. During the period of the kingdom rule in Israel, prophets did act as public spokesmen proclaiming God’s decrees, judgments, and summonses in public places. (Isa 58:1; Jer 26:2) Jonah’s proclamation to Nineveh fits well the thought conveyed by keʹryg·ma, and it is so described. (Compare Jon 3:1-4; Mt 12:41.) The prophets’ ministry, however, generally was much broader than that of a herald or preacher, and in some cases they employed others to act as their spokesmen. (2Ki 5:10; 9:1-3; Jer 36:4-6) Some of their messages and visions were written rather than orally proclaimed (Jer 29:1, 30, 31; 30:1, 2; Da chaps 7-12); many were given in private audience, and the prophets also used symbolic acts to convey ideas.​—See PROPHECY; PROPHET.

Admonition, warnings, and judgments were proclaimed, and so was good news​—of victories, deliverance, and blessings—​as well as praises to Jehovah God. (1Ch 16:23; Isa 41:27; 52:7; the Hebrew ba·sarʹ is used in these texts.) At times women cried out or sang the news of battles won or of coming relief.​—Ps 68:11; Isa 40:9; compare 1Sa 18:6, 7.

The Hebrew Scriptures also pointed forward to the preaching work that would be done by Christ Jesus and the Christian congregation. Jesus quoted Isaiah 61:1, 2 as foretelling his divine commission and his authorization to preach. (Lu 4:16-21) In fulfillment of Psalm 40:9 (the preceding verses being applied to Jesus by the apostle Paul at Heb 10:5-10), Jesus “told the good news [form of ba·sarʹ] of righteousness in the big congregation.” The apostle Paul quoted Isaiah 52:7 (concerning  the messenger bringing the news of Zion’s release from its captive state) and related it to the public preaching work of Christians.​—Ro 10:11-15.

In the Christian Greek Scriptures. Though active primarily in the wilderness regions, John the Baptizer did the work of a preacher or public messenger, heralding the approach of the Messiah and God’s Kingdom to the Jews who came out to him and summoning them to repentance. (Mt 3:1-3, 11, 12; Mr 1:1-4; Lu 3:7-9) At the same time John served as a prophet, a teacher (with disciples), and an evangelizer. (Lu 1:76, 77; 3:18; 11:1; Joh 1:35) He was “a representative of God” and His witness.​—Joh 1:6, 7.

Jesus did not remain in the wilderness region of Judea after his 40-day fast there, nor did he isolate himself as in a monastic life. He recognized that his divine commission called for a preaching work, and he carried it on publicly, in cities and villages, in the temple area, synagogues, marketplaces and streets, as well as in the countryside. (Mr 1:39; 6:56; Lu 8:1; 13:26; Joh 18:20) Like John, he did more than preach. His teaching receives even greater emphasis than his preaching. Teaching (di·daʹsko) differs from preaching in that the teacher does more than proclaim; he instructs, explains, shows things by argument, and offers proofs. The work of Jesus’ disciples, both before and after his death, was thus to be a combination of preaching and teaching.​—Mt 4:23; 11:1; 28:18-20.

The theme of Jesus’ preaching was: ‘Repent, for the kingdom of the heavens has drawn near.’ (Mt 4:17) Like an official herald, he was alerting his listeners to his Sovereign God’s activity, to a time of opportunity and decision. (Mr 1:14, 15) As foretold by Isaiah, not only did he bring good news and comfort for the meek, brokenhearted, and mourning ones, as well as proclaim release to captives, but he also declared “the day of vengeance on the part of our God.” (Isa 61:2) He boldly announced God’s purposes, decrees, appointments, and judgments before rulers and people.

Following Jesus’ Death. After his death, and particularly from Pentecost of 33 C.E. onward, Jesus’ disciples carried on the preaching work, first among the Jews and eventually to all the nations. Anointed by holy spirit, they recognized and repeatedly informed their listeners that they were authorized heralds (Ac 2:14-18; 10:40-42; 13:47; 14:3; compare Ro 10:15), even as Jesus had stressed that he was ‘sent by God’ (Lu 9:48; Joh 5:36, 37; 6:38; 8:18, 26, 42), who gave him “a commandment as to what to tell and what to speak.” (Joh 12:49) Therefore, when ordered to cease their preaching, the disciples’ reply was: “Whether it is righteous in the sight of God to listen to you rather than to God, judge for yourselves. But as for us, we cannot stop speaking about the things we have seen and heard.” “We must obey God as ruler rather than men.” (Ac 4:19, 20; 5:29, 32, 42) This preaching activity was an essential part of their worship, a means of praising God, a requisite to the gaining of salvation. (Ro 10:9, 10; 1Co 9:16; Heb 13:15; compare Lu 12:8.) As such, it was to be shared in by all disciples, men and women, down till “the conclusion of the system of things.”​—Mt 28:18-20; Lu 24:46-49; Ac 2:17; compare Ac 18:26; 21:9; Ro 16:3.

These early Christian preachers were not highly educated men by worldly standards. The Sanhedrin perceived the apostles Peter and John to be “men unlettered and ordinary.” (Ac 4:13) Concerning Jesus himself, “the Jews fell to wondering, saying: ‘How does this man have a knowledge of letters, when he has not studied at the schools?’” (Joh 7:15) Secular historians noted the same points. “Celsus, the first writer against Christianity, makes it a matter of mockery, that labourers, shoemakers, farmers, the most uninformed and clownish of men, should be zealous preachers of the Gospel.” (The History of the Christian Religion and Church, During the Three First Centuries, by Augustus Neander; translated from the German by Henry John Rose, 1848, p. 41) Paul explained it in this way: “For you behold his calling of you, brothers, that not many wise in a fleshly way were called, not many powerful, not many of noble birth; but God chose the foolish things of the world, that he might put the wise men to shame.”​—1Co 1:26, 27.

However, although not highly educated in worldly schools, the early Christian preachers were not untrained. Jesus gave extensive training to the 12 apostles before he sent them out to preach. (Mt 10) This training was not just the giving of instructions, but it was a practical training.​—Lu 8:1.

The theme of Christian preaching continued to be “the kingdom of God.” (Ac 20:25; 28:31) However, their proclamation contained added features as compared with that made prior to Christ’s death. “The sacred secret” of God’s purpose had been revealed through Christ; his sacrificial death had become a vital factor in true faith (1Co 15:12-14); his exalted position as God’s assigned King and Judge must be known, recognized, and submitted to by all who would gain divine favor and life. (2Co 4:5) Thus, the disciples are often  spoken of as ‘preaching Christ Jesus.’ (Ac 8:5; 9:20; 19:13; 1Co 1:23) An examination of their preaching makes clear that their ‘preaching Christ’ was not done so as to isolate him in the minds of their listeners as though he were somehow independent or detached from God’s Kingdom arrangement and overall purpose. Rather, they proclaimed what Jehovah God had done for and through his Son, how God’s purposes were being fulfilled and would be fulfilled in Jesus. (2Co 1:19-21) Thus, all such preaching was to God’s own praise and glory, “through Jesus Christ.”​—Ro 16:25-27.

Their preaching was not performed simply as a duty, nor did their heralding consist merely of speaking out a message in a formal way. It sprang from heartfelt faith and was done with the desire to honor God and with the loving hope of bringing salvation to others. (Ro 10:9-14; 1Co 9:27; 2Co 4:13) Therefore the preachers were willing to be treated as foolish by the worldly wise or be persecuted as heretics by the Jews. (1Co 1:21-24; Ga 5:11) For this reason, too, their preaching was accompanied by the use of reasoning and persuasion to help the hearers to believe and exercise faith. (Ac 17:2; 28:23; 1Co 15:11) Paul speaks of himself as being appointed “a preacher and apostle and teacher.” (2Ti 1:11) These Christians were not salaried heralds but were dedicated worshipers giving of themselves, giving their time and their strength to the preaching activity.​—1Th 2:9.

Since all who became disciples also became preachers of the Word, the good news spread rapidly, and by the time Paul wrote his letter to the Colossians (c. 60-61 C.E. or about 27 years after Christ’s death), he could speak of the good news “which was preached in all creation that is under heaven.” (Col 1:23) Hence, Christ’s prophecy of the ‘preaching of the good news in all the nations’ saw a certain fulfillment prior to the destruction of Jerusalem and its temple in 70 C.E. (Mt 24:14; Mr 13:10; MAP, Vol. 2, p. 744) Jesus’ own words, as well as the book of Revelation, written after that destruction, point to a greater fulfillment of this prophecy at the time of Christ’s beginning to exercise Kingdom rule and preliminary to the destruction of all adversaries of that Kingdom, a logical time for a great heralding work to be accomplished.​—Re 12:7-12, 17; 14:6, 7; 19:5, 6; 22:17.

What results should Christian preachers expect for their efforts? Paul’s experience was that “some began to believe the things said; others would not believe.” (Ac 28:24) Real Christian preaching, based on God’s Word, requires a response of some kind. It is vigorous, dynamic, and above all, it presents an issue on which people must take sides. Some become active opposers of the Kingdom message. (Ac 13:50; 18:5, 6) Others listen for a time, but eventually they turn back for various reasons. (Joh 6:65, 66) Still others accept the good news and act upon it.​—Ac 17:11; Lu 8:15.

“From House to House.” Jesus went right to the people with the Kingdom message, teaching them publicly and in their homes. (Mt 5:1; 9:10, 28, 35) When he sent out his early disciples to preach, he directed them: “Into whatever city or village you enter, search out who in it is deserving.” (Mt 10:7, 11-14) Such ‘searching out’ would reasonably include going to the people’s homes, where “deserving” persons would heed the message and the disciples would find lodging for the night.​—Lu 9:1-6.

On a later occasion Jesus “designated seventy others and sent them forth by twos in advance of him into every city and place to which he himself was going to come.” These were not just to preach in public places but were also to contact people at their homes. Jesus instructed them: “Wherever you enter into a house say first, ‘May this house have peace.’”​—Lu 10:1-7.

In the days following Pentecost 33 C.E., Jesus’ disciples continued bringing the good news right to the homes of the people. Though ordered to “stop speaking,” the inspired record says that “every day in the temple and from house to house they continued without letup teaching and declaring the good news about the Christ, Jesus.” (Ac 5:40-42; compare Dy, NIV.) The expression “from house to house” translates the Greek katʼ oiʹkon, literally, “according to house”; the sense of the Greek preposition ka·taʹ is distributive (“from house to house”) and not merely adverbial (‘at home’). (See NW ftn.) This method of reaching people​—going directly to their homes—​brought outstanding results. “The number of the disciples kept multiplying in Jerusalem very much.”​—Ac 6:7; compare 4:16, 17 and 5:28.

The apostle Paul told the elders of Ephesus: “From the first day that I stepped into the district of Asia . . . I did not hold back from telling you any of the things that were profitable nor from teaching you publicly and from house to house. But I thoroughly bore witness both to Jews and to Greeks about repentance toward God and faith in our Lord Jesus.” (Ac 20:18-21; compare KJ, Dy, AS, RS, Mo, NIV, La.) Paul was here speaking of his efforts to preach to these men when they were yet unbelievers, persons needing to know “about repentance toward God and faith in our Lord Jesus.”  Thus, from the start of his missionary service in Asia, Paul searched “from house to house” for spiritually inclined persons. Finding such ones, he doubtless returned to their homes to teach them further and, as these became believers, to strengthen them in the faith. Dr. A. T. Robertson, in his book Word Pictures in the New Testament, comments as follows on Acts 20:20: “By (according to) houses. It is worth noting that this greatest of all preachers preached from house to house and did not make his visits mere social calls.”​—1930, Vol. III, pp. 349, 350.

Preaching Within the Congregation. Most preaching activity recorded in the Christian Greek Scriptures relates to the proclamation done outside the congregation. However, Paul’s exhortation to Timothy to “preach the word, be at it urgently in favorable season, in troublesome season,” includes preaching within the congregation, as done by a general overseer. (2Ti 4:2) Paul’s letter to Timothy is a pastoral letter, that is, it was directed to one who was doing pastoral work among the Christians and provides counsel on such superintending ministry. Previous to this exhortation to “preach the word,” Paul warned Timothy of the apostasy beginning to manifest itself, which was to develop to serious proportions. (2Ti 2:16-19; 3:1-7) Following up his exhortation to Timothy to hold to and not be sidetracked from “the word” in his preaching, Paul shows the need for the urgency, saying, “for there will be a period of time when they will not put up with the healthful teaching” but, rather, will seek teachers who teach according to their own desires and so will “turn their ears away from the truth,” hence describing, not outsiders, but those within the congregation. (2Ti 4:3, 4) Timothy, therefore, was not to lose his spiritual balance but was to be constant in boldly declaring God’s Word (not human philosophies or useless speculations) to the brothers, even though this might bring him trouble and suffering from those wrongly inclined within the congregations. (Compare 1Ti 6:3-5, 20, 21; 2Ti 1:6-8, 13; 2:1-3, 14, 15, 23-26; 3:14-17; 4:5.) By so doing, he would act as a deterrent to the apostasy and be free of responsibility for bloodguilt, even as Paul had been.​—Ac 20:25-32.

What was the objective of Jesus’ preaching “to the spirits in prison”?

At 1 Peter 3:19, 20, after describing Jesus’ resurrection to spirit life, the apostle says: “In this state also he went his way and preached to the spirits in prison, who had once been disobedient when the patience of God was waiting in Noah’s days, while the ark was being constructed.” Commenting on this text, Vine’s Expository Dictionary of Old and New Testament Words says: “In I Pet. 3:19 the probable reference is, not to glad tidings (which there is no real evidence that Noah preached, nor is there evidence that the spirits of antediluvian people are actually ‘in prison’), but to the act of Christ after His resurrection in proclaiming His victory to fallen angelic spirits.” (1981, Vol. 3, p. 201) As has been noted, ke·rysʹso refers to a proclamation that may be not only of something good but also of something bad, as when Jonah proclaimed Nineveh’s coming destruction. The only imprisoned spirits referred to in the Scriptures are those angels of Noah’s day who were ‘delivered into pits of dense darkness’ (2Pe 2:4, 5) and “reserved with eternal bonds under dense darkness for the judgment of the great day.” (Jude 6) Therefore the preaching by the resurrected Jesus to such unrighteous angels could only have been a preaching of judgment. It may be noted that the book of Revelation transmitted in vision to John by Christ Jesus toward the close of the first century C.E. contains much about Satan the Devil and his demons as well as their ultimate destruction, hence, a preaching of judgment. (Re 12-20) Peter’s use of the past tense (“preached”) indicates that such preaching had been done prior to the writing of his first letter.