“The feasts of the Lord, even holy convocations, which ye shall
proclaim in their seasons” (Lev. xxiii. 4), are Passover, Feast of
Weeks, Day of Memorial, Day of Atonement, and Feast of Tabernacles.
These are divided into two groups called שלוש רגלים and ימים
נוראים, “three festivals” and “solemn days.” In the Pentateuch the two
groups are kept distinctly asunder. Thus in Exod. xxiii. 14–17 and
xxxiv. 18, and Deut. xvi., only the former group is mentioned.
The name shalosh regalim derives its origin from the following Biblical
passage: “Three times thou shalt keep a feast unto me in the year,”
שלש רגלים תחג לי בשנה (Exod. xxiii. 14). Although in a parallel
passage the word רגלים has been replaced by פעמים (ibid. ver. 17),
of the same meaning, “times,” shalosh regalim has been preferred,
because רגלים reminds one also of “a journey on foot,” “a
pilgrimage,” an important element in the celebration of these three
festivals, according to the Divine commandment, “Three times every year
shall thy males appear before the Lord thy God, in the place which he
shall choose, in the feast of unleavened bread, in the feast of weeks,
and in the feast of tabernacles” (Deut. xvi. 16).
The name yamim noraim for the remaining two feasts is not founded on a
Biblical phrase, but on the fact that these festivals are devoted more
than the rest to earnest reflection and solemn devotion.