Leviticus 23:2

Speak unto the children of Israel and say unto them, Concerning the feasts of the Lord which ye shall proclaim to be holy convocations, even these are My feasts. The word originally means fixed or appointed times, which the Lord had marked out, separated, distinguished from the ordinary course of daily life, and therefore found its chief application in the case of the festivals. While the Chapter contains a calendar of the festivals, its purpose is chiefly, as the restricting relative clause indicates, to mark those festivals upon which there should be solemn meetings for the purpose of worship.