Parashas Mishpatim · Passuk 23:14
Chabad.org — English translation + Rashi
Torah Temimah points to Mechilta (verified).
Sefaria — Exodus 23:14
Sefaria — Mechilta
English: Why does the verse mention the three pilgrimage festivals in the section of shemitah? To teach that the three festivals are not displaced from their appointed times.
In context: See the cited source for the full section.
Derash on the verse.