80:17-19 The Messiah, the Protector and Saviour of the church, is the Man of God's right hand; he is the Arm of the Lord, for all power is given to him. In him is our strength, by which we are enabled to persevere to the end. The vine, therefore, cannot be ruined, nor can any fruitful branch perish; but the unfruitful will be cut off and cast into the fire. The end of our redemption is, that we should serve Him who hath redeemed us, and not go back to our old sins.

17. thy hand … upon—that is, strengthen (Ezr 7:6; 8:22).

man of … hand—may allude to Benjamin (Ge 35:18). The terms in the latter clause correspond with those of Ps 80:15, from "and the branch," &c., literally, and confirm the exposition given above.