Exodus 23:15

(15) The feast of unleavened bread.—See the Notes on Exodus 12:15-20.

In the time appointed of the month Abib.—From the 14th day of the month Abib (or Nisan) to the 21st day. (See Exo. Xii. 18, 13:4-7.)

None shall appear before me empty.—Viewed religiously, the festivals were annual national thanks-givings for mercies received, both natural and miraculous—the first for the commencement of harvest and the deliverance out of Egypt; the second for the completion of the grain-harvest and the passage of the Red Sea; the third for the final gathering in of the fruits and the many mercies of the wilderness. At such seasons we must not “appear before God empty,” we must give Him not only “the salves of our lips,” but some substantial acknowledgment of His goodness towards us. The law here laid down with respect to the first feast is afterwards extended to the other two (Deuteronomy 16:16).