John Gill Commentary 1 Kings 8:56

"Blessed be Jehovah, that hath given rest unto his people Israel, according to all that he promised: there hath not failed one word of all his good promise, which he promised by Moses his servant." — 1 Kings 8:56 (ASV)

Blessed be the Lord, that has given rest unto his people
Israel, according, to all that he promised
&c.] A land of rest, and rest in the land from all enemies; see (Deuteronomy 12:9Deuteronomy 12:10) ,

there has not failed one word of all his good promises, which he
promised by the hand of Moses his servant :
so Joshua observed a little before his death, (Joshua 23:14) to which Solomon seems to have respect; and who lived to see a greater accomplishment of the gracious promises of God, and his faithfulness therein, both in the times of his father David, and his own.