John Gill Commentary Exodus 13:5

"And it shall be, when Jehovah shall bring thee into the land of the Canaanite, and the Hittite, and the Amorite, and the Hivite, and the Jebusite, which he sware unto thy fathers to give thee, a land flowing with milk and honey, that thou shalt keep this service in this month." — Exodus 13:5 (ASV)

And it shall be when the Lord shall bring you into the land of the Canaanites. Though the whole land was called the land of Canaan, yet there was one tribe or nation of them particularly so called as here, distinct from those that follow: and the Hittites, and the Amorites, and the Hivites, and the Jebusites; there were seven nations in all, but two are here omitted, the Girgashites and Perizzites, but they are added in the Septuagint version, see (Deuteronomy 7:1).

which he swore unto your fathers to give you; to Abraham, Isaac, and Jacob; so that they might be assured they would be brought into it, since they had both the word and oath of God for it; and which is the rather mentioned now for their encouragement, since they were at this time set forward in their journey thitherwards: a land flowing with milk and honey; (See Gill on Exodus 3:8).

that you shall keep this service in this month; the month of Abib; that is, the following service concerning unleavened bread; it is concluded from hence by some, that those laws concerning the passover, and eating unleavened bread, and sanctifying the firstborn, did not oblige the Israelites, while in the wilderness, only when they came into the land of Canaan; and it seems pretty clear that this was the case with respect to the two latter, but not the former, since it is certain they did keep the passover in the wilderness, and were obliged to it, (Numbers 9:1–5) but then it may be observed, that there is no mention there of their keeping the feast of unleavened bread, only of the passover, as here no mention is made of the feast of the passover, which, though they followed one another, were, two distinct feasts.