Deuteronomy 32:40Meaning & Commentary from the Church Fathers

The mystery of the Son serves as the focal point of the Father’s divine promise. It is customary for the Father to affirm His commitment as if by His own might—through the Son. This signifies swearing by Himself, for the Son is not separate from Him regarding the essence and identity of the Divine Nature. Accordingly, the holy Moses communicates God’s oath with clarity, stating: “I lift up My hand to heaven, and ... I say, I live forever.” The Son embodies the right hand of God, through whom the Father governs all creation, sustaining everything within His grasp, enacting divine works, calling forth that which does not exist, and graciously enriching that which has already come into being.

Moses declares, "I lift up my hand to heaven," referring to the Lord's hands, which were pure and crucified. When he proclaims, "And I swear by my right hand, and say, I live forever!" he is alluding to the resurrection of the Lord.