Deuteronomy 31:21

21 And when many disasters and calamities come on them, this song will testify against them, because it will not be forgotten by their descendants. I know what they are disposed to do, even before I bring them into the land I promised them on oath.”

Read Deuteronomy 31:21 Using Other Translations

And it shall come to pass, when many evils and troubles are befallen them, that this song shall testify against them as a witness; for it shall not be forgotten out of the mouths of their seed: for I know their imagination which they go about, even now, before I have brought them into the land which I sware.
And when many evils and troubles have come upon them, this song shall confront them as a witness (for it will live unforgotten in the mouths of their offspring). For I know what they are inclined to do even today, before I have brought them into the land that I swore to give."
And when great disasters come down on them, this song will stand as evidence against them, for it will never be forgotten by their descendants. I know the intentions of these people, even now before they have entered the land I swore to give them.”

What does Deuteronomy 31:21 mean?

John Gill's Exposition of the Bible
Deuteronomy 31:21

And it shall come to pass, when many evils and troubles are
befallen them
As did in the times of the judges, in the Babylonish captivity, and do now in their present exile:

that this song shall testify against them as a witness;
which so clearly points at their sins, with all their aggravated circumstances, and describes so fully their calamities, distresses, and punishment for them:

for it shall not be forgotten out of the mouths of their seed;
which shows that it respects time to come, their later posterity, whose memory of this song would be conjured up by the evils that should come upon them for their sins; nor is it forgotten by them to this day, who acknowledge there are some things in it now fulfilled or fulfilling in them:

for I know their imagination which they go about even now:
or are "making" F3; forming and framing within themselves, there being a secret inclination in their minds to idolatry, which were working and contriving schemes to bring it about, and set it up; and this, God, the searcher of hearts, knew full well, and that in process of time this evil imagination would break forth into act, in an open and flagrant manner:

before I have brought thee into the land which I sware;
to their fathers, to give it to them for an inheritance, as is suggested in ( Deuteronomy 31:20 ) .


FOOTNOTES:

F3 (hve) "faciens", Montanus; "quam facit", Pagninus.
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