A gathering or meeting together of people for a specific purpose; an assembly. In the Scriptures the term “convention” is a translation of the Hebrew word miq·raʼʹ, meaning “a calling together,” or “convening; convoking.” An alternate rendering of this Hebrew word is “convocation.” Bearing out its basic meaning is its use at Numbers 10:2 to convey the thought of convening the assembly of Israel.​—Compare Isa 1:13, ftn.

The “holy conventions” were scheduled as follows: (1) Every Sabbath (Le 23:3); (2) the first and seventh days of the Festival of Unfermented Cakes during Nisan, the first month (March-April) (Nu 28:18, 25; Le 23:6-8); (3) the Festival of Weeks or Festival of Harvest, later known as Pentecost,  held in the third month, Sivan (May-June) (Le 23:15-21); (4) the first and tenth days of the seventh month, Ethanim or Tishri (September-October), the latter day being the Day of Atonement (Le 23:23-27; Nu 29:1, 7); (5) the first day of the Festival of Booths, which began on the 15th day of the seventh month, Ethanim or Tishri, also the day after that seven-day festival.​—Le 23:33-36.

A unique feature of all of these “holy conventions” was that during them the people were to do no laborious work. For instance, the first and seventh days of the Festival of Unfermented Cakes were “holy conventions,” concerning which Jehovah stated: “No work is to be done on them. Only what every soul needs to eat, that alone may be done for you.” (Ex 12:15, 16) However, during “holy conventions” the priests were busy offering sacrifices to Jehovah (Le 23:37, 38), certainly no violation of any command against doing normal daily work. These occasions were not periods of idleness for the people in general either but were times of great spiritual benefit. On the weekly Sabbath day, the people met together for public worship and instruction. They were then edified by the public reading and explanation of God’s written Word, as in the later synagogues. (Ac 15:21) Therefore, while the people did not do laborious work during the Sabbath day or the other “holy conventions,” they would then devote themselves to prayer and meditation on the Creator and his purposes.​—See ASSEMBLY.