Neither turned away back "Neither did I withdraw myself backward" - Eleven MSS. and the oldest edition prefix the conjunction ו vau ; and so also the Septuagint and Syriac.
The Lord God hath opened mine ear - This is another expression denoting that he was attentive to the import of the divine commission (see Psalm 40:6).
And I was not rebellious - I willingly undertook the task of communicating the divine will to mankind. The statement here is in accordance with all that is said of the Messiah, that he was willing to come and do the will of God, and that whatever trials the work involved he was prepared to meet them (see Psalm 40:6-8; compare Hebrews 10:4-10).