18 In the first month, on the fourteenth day of the month at even, ye shall eat unleavened bread, until the one and twentieth day of the month at even.
Unleavened bread: By this it appears, that our Saviour made use of unleavened bread, in the institution of the blessed sacrament, which was on the evening of the paschal solemnity, at which time there was no leavened bread to be found in Israel.
[AD 1781] Richard Challoner on Exodus 12:18