John Gill Commentary Deuteronomy 8:12

"lest, when thou hast eaten and art full, and hast built goodly houses, and dwelt therein;" — Deuteronomy 8:12 (ASV)

Lest when you have eaten and are full
Not only once and again, but continually, day after day, being indulged with great plenty:

and have built goodly houses, and dwelt [therein] ;
who for forty years had only dwelt in tents, moving from place to place in the wilderness.