Thomas Aquinas, on Ps 33:2

“I will bless the Lord at all times, his praise shall be always in my mouth.”

“Then when he says, "In the Lord," the fruit of praise is presented. He says therefore, "In the Lord my soul shall be praised." For one always regards the good of a friend as one's own good. Hence he says, the praise of God is also my praise. If God is great, it is certain that his friend is great: Ps. 117: "The Lord is my strength and my praise." And he says "soul," because spiritual joy principally pertains to it. Next, when he says, "Let the meek hear," he leads others first to the cause of praise. Second, to the praise itself, at "Magnify." The beginning of praise is interior joy; hence he says, "Let the meek hear." And therefore they rejoice in all things that are of God, because the harsh do not rejoice but rebel. And he says, "Let them hear," because this joy comes from hearing of others who act well.”

Imported from an open dataset — not yet checked against the printed edition.