John Gill Commentary Deuteronomy 8:14

"then thy heart be lifted up, and thou forget Jehovah thy God, who brought thee forth out of the land of Egypt, out of the house of bondage;" — Deuteronomy 8:14 (ASV)

Then your heart be lifted up
As the heart is apt to be when riches increase; hence the advice in (1 Timothy 6:17)

and you forget the Lord your God ;
from whom all good things come, and who can take them away when he pleases, and therefore should be ever kept in mind, for ever looked to and trusted in for the continuance of them; yet such is the evil heart of man, and such the stupefying nature of riches, that they bring on forgetfulness of the author of them, lead off from dependence on him and obedience to him; in order to prevent which, an enumeration is given of wonderful instances of divine goodness to Israel, as follows:

which brought you forth out of the land of Egypt, from the house of
bondage ;
into a land abounding with all the above good things, and therefore it must be the highest ingratitude to forget such a God, and disobey his commands.