4 The Rock, his work is perfect, and all his ways are just. A faithful God, without deceit, just and upright is he;

Matthew Henry's Commentary on Deuteronomy 32:4

Commentary on Deuteronomy 32:3-6

(Read Deuteronomy 32:3-6)

"He is a Rock." This is the first time God is called so in Scripture. The expression denotes that the Divine power, faithfulness, and love, as revealed in Christ and the gospel, form a foundation which cannot be changed or moved, on which we may build our hopes of happiness. And under his protection we may find refuge from all our enemies, and in all our troubles; as the rocks in those countries sheltered from the burning rays of the sun, and from tempests, or were fortresses from the enemy. "His work is perfect:" that of redemption and salvation, in which there is a display of all the Divine perfection, complete in all its parts. All God's dealings with his creatures are regulated by wisdom which cannot err, and perfect justice. He is indeed just and right; he takes care that none shall lose by him. A high charge is exhibited against Israel. Even God's children have their spots, while in this imperfect state; for if we say we have no sin, no spot, we deceive ourselves. But the sin of Israel was not habitual, notorious, unrepented sin; which is a certain mark of the children of Satan. They were fools to forsake their mercies for lying vanities. All wilful sinners, especially sinners in Israel, are unwise and ungrateful.