18 In the first month, on the fourteenth day of the month at evening, you shall eat unleavened bread, until the twenty first day of the month at evening.
Exodus 12:18 Cross References - WEB
Exodus 12:1-2
Exodus 12:15
15 “‘Seven days you shall eat unleavened bread; even the first day you shall put away yeast out of your houses, for whoever eats leavened bread from the first day until the seventh day, that soul shall be cut off from Israel.
Leviticus 23:5-8
5 In the first month, on the fourteenth day of the month in the evening, is Yahweh’s Passover.
6 On the fifteenth day of the same month is the feast of unleavened bread to Yahweh. Seven days you shall eat unleavened bread.
7 In the first day you shall have a holy convocation. You shall do no regular work.
8 But you shall offer an offering made by fire to Yahweh seven days. In the seventh day is a holy convocation. You shall do no regular work.’”
Numbers 28:16-25
16 “‘In the first month, on the fourteenth day of the month, is Yahweh’s Passover.
17 On the fifteenth day of this month shall be a feast. Unleavened bread shall be eaten for seven days.
18 In the first day shall be a holy convocation. You shall do no regular work,
19 but you shall offer an offering made by fire, a burnt offering to Yahweh: two young bulls, one ram, and seven male lambs a year old. They shall be without defect,
20 with their meal offering, fine flour mixed with oil. You shall offer three tenths for a bull, and two tenths for the ram.
21 You shall offer one tenth for every lamb of the seven lambs;
22 and one male goat for a sin offering, to make atonement for you.
23 You shall offer these in addition to the burnt offering of the morning, which is for a continual burnt offering.
24 In this way you shall offer daily, for seven days, the food of the offering made by fire, of a pleasant aroma to Yahweh. It shall be offered in addition to the continual burnt offering and its drink offering.
25 On the seventh day you shall have a holy convocation. You shall do no regular work.