Adam Clarke on Galatians 2:20

I am crucified with Christ - The death of Christ on the cross has showed me that there is no hope of salvation by the law; I am therefore as truly dead to all expectation of justification by the law, as Christ was dead when he gave up the ghost upon the cross. Through him alone I live - enjoy a present life, and have a prospect of future glory.

Yet not I - It is not of my natural life I speak, nor of any spiritual things which I myself have procured; but Christ liveth in me. God made man to be a habitation of his own Spirit: the law cannot live in me so as to give me a Divine life; it does not animate, but kill; but Christ lives in me; he is the soul of my soul; so that I now live to God. But this life I have by the faith of the Son of God - by believing on Christ as a sacrifice for sin; for he loved me, and because he did so he gave himself for me - made himself a sacrifice unto death, that I might be saved from the bitter pains of death eternal.