50:4-9 As Jesus was God and man in one person, we find him sometimes speaking, or spoken of, as the Lord God; at other times, as man and the servant of Jehovah. He was to declare the truths which comfort the broken, contrite heart, those weary of sin, harassed with afflictions. And as the Holy Spirit was upon him, that he might speak as never man spake; so the same Divine influence daily wakened him to pray, to preach the gospel, and to receive and deliver the whole will of the Father. The Father justified the Son when he accepted the satisfaction he made for the sin of man. Christ speaks in the name of all believers. Who dares to be an enemy to those unto whom he is a Friend? or who will contend with those whom he is an Advocate? Thus St. Paul applies it, Ro 8:33.
4. Messiah, as "the servant of Jehovah" (Isa 42:1), declares that the office has been assigned to Him of encouraging the "weary" exiles of Israel by "words in season" suited to their case; and that, whatever suffering it is to cost Himself, He does not shrink from it (Isa 50:5, 6), for that He knows His cause will triumph at last (Isa 50:7, 8).
learned—not in mere human learning, but in divinely taught modes of instruction and eloquence (Isa 49:2; Ex 4:11; Mt 7:28, 29; 13:54).
speak a word in season—(Pr 15:23; 25:11). Literally, "to succor by words," namely, in their season of need, the "weary" dispersed ones of Israel (De 28:65-67). Also, the spiritual "weary" (Isa 42:3; Mt 11:28).
wakeneth morning by morning, &c.—Compare "daily rising up early" (Jer 7:25; Mr 1:35). The image is drawn from a master wakening his pupils early for instruction.
wakeneth … ear—prepares me for receiving His divine instructions.
as the learned—as one taught by Him. He "learned obedience," experimentally, "by the things which He suffered"; thus gaining that practical learning which adapted Him for "speaking a word in season" to suffering men (Heb 5:8).