John Lightfoot on Luke 20:42

[The Lord said unto my Lord, &c.] Whereas St. Matthew tells us, That "no man was able to answer him a word" to that argument, whereby he asserted the divinity of the Messias, it is plain that those evasions were not yet thought of, by which the Jews have since endeavoured to shift off this place. For the Talmudists apply the psalm to Abraham; the Targumist (as it seems) to David; others (as Justin Martyr tells us) to Hezekiah; which yet I do not remember I have observed in the Jewish authors. His words are in his Dialogue with Tryphon: I am not ignorant, that you venture to explain this psalm (when he had recited the whole psalm) as if it were to be understood of king Hezekiah.

The Jewish authors have it thus: "Sem the Great said unto Eliezer [Abraham's servant], 'When the kings of the east and of the west came against you, what did you?' He answered and said, 'The Holy Blessed God took Abraham, and made him to sit on his right hand.'" And again: "The Holy Blessed God had purposed to have derived the priesthood from Shem; according as it is said, Thou art the priest of the most high God: but because he blessed Abraham before he blessed God, God derived the priesthood from Abraham. For so it is said, And he blessed him and said, Blessed be Abraham of the most high God, possessor of heaven and earth, and blessed be the most high God. Abraham saith unto him, Who useth to bless the servant before his Lord? Upon this God gave the priesthood to Abraham, according as it is said, The Lord said unto my Lord, Sit thou on my right hand. And afterward it is written, The Lord sware and will not repent, Thou art a priest for ever for the speaking of Melchizedek." Midras Tillin and others also, in the explication of this psalm, refer it to Abraham. Worshipful commentators indeed!