Deuteronomy 8:19

19 If you ever forget the Lord your God and go after other gods to worship and bow down to them, I testify against you today that you will perish.

Deuteronomy 8:19 Meaning and Commentary

Deuteronomy 8:19

And it shall be, if thou do at all forget the Lord thy God,
&c.] Either the mercies they received from him, not acknowledging they came from him, but ascribing them to themselves; or their duty to him, to whom they were so greatly obliged: and walk after other gods, and serve them, and worship them; which would be to forget him indeed, forsaking his worship, and giving homage and adoration to idols, which is what is intended by these expressions:

I testify against you this day that ye shall surely perish;
by one judgment and calamity or another, as the sword, famine, pestilence, and captivity; there being nothing more provoking to God than idolatry, which so much detracts from his honour and glory: and which besides, in such a people, so highly favoured of God, it argued the basest ingratitude.

Deuteronomy 8:19 In-Context

17 You may say to yourself, 'My power and my own ability have gained this wealth for me,'

18 but remember that the Lord your God gives you the power to gain wealth, in order to confirm His covenant He swore to your fathers, as it is today.

19 If you ever forget the Lord your God and go after other gods to worship and bow down to them, I testify against you today that you will perish.

20 Like the nations the Lord is about to destroy before you, you will perish if you do not obey the Lord your God.