Days of Unleavened Bread
The seven days following Passover — Nisan 15 through 21 — when leaven is put out and only unleavened bread is eaten (Lev 23:6). Scripture calls that bread the “bread of affliction,” tied to leaving Egypt in haste (Deut 16:3) — a fuller sense than leaven simply standing for sin. Synonyms: Feast of Unleavened Bread, Unleavened Bread, ULB.