Albert Barnes Commentary Psalms 115:12

"Jehovah hath been mindful of us; he will bless [us]: He will bless the house of Israel; He will bless the house of Aaron." — Psalms 115:12 (ASV)

The LORD has been mindful of us—this would be especially appropriate if the psalm was written, as is commonly supposed, after the return from the Babylonian captivity. In such circumstances, it would be in every way proper to bring to the minds of the people the fact that God had remembered them and had delivered them.

He will bless us—our past experience provides the fullest evidence that he will continue to bless us. He who has delivered us from such great calamities, and who has restored us to our native land after such a long and painful captivity, will not forsake us now.

There can now be no circumstances in which he cannot bestow upon us all the blessings we need; there will be none in which we may not hope that he will bless us. If he could save us from such troubles, he can save us from all; if he intervened in this way, we may argue that he will always grant us his help when we need it.

He will bless the house of Israel; he will bless the house of Aaron—compare Psalm 115:9-10.