John Calvin Commentary Isaiah 50:5

"The Lord Jehovah hath opened mine ear, and I was not rebellious, neither turned away backward." — Isaiah 50:5 (ASV)

The Lord Jehovah hath opened mine ear. He again repeats what he had previously said, and here includes everything that belongs to the office of a teacher. For the “opening of the ear” must be understood to refer not only to doctrine but also to the whole calling; that is, when he takes someone to be his servant, informs the one whom he has determined to send of his duty, gives commands, and directs him to carry out what he commands. But the Lord “opens the ear” not only when he declares what is his will, but also when he powerfully affects a person’s heart and moves him to render obedience, as it is said:

Thou hast bored mine ear (Psalms 40:6).

And Christ says:

Whosoever hath heard and learned from the Father cometh to me (John 6:45).

Such is also the import of the second clause, And I was not rebellious, the meaning of which may be thus summed up: “He undertakes nothing at random, but, being fully convinced of God’s calling, he discharges the office of a teacher, though it is laborious and difficult, because he is ready to obey.”