John Gill Bible Commentary

Ye shall not do after all the things that we do here,.... In the wilderness, where they had no abiding, but were continually removing from place to place, and could not always observe punctually and precisely the exact order and time of their sacrifices and other things, nor offer them at any certain place, and many were doubtless neglected by them; see Amo 5:25. every man whatsoever is right in his own eyes; that did he, brought the above things when and where he pleased; not that there was no regard had to the laws and rules given, as if there was no priest in Israel; but they were not so exactly in all circumstances conformed to as they would be obliged to when they came into the land of Canaan, and had a certain place to bring their offerings to; so some in Aben Ezra observe, that one would give the firstling, another not, because it depended on the land, or was what they were obliged to only when they came into the land of Canaan; see Exo 13:11 but he thinks the sense is, that they did not all fear God, and so did not do their duty.