Robert Murray M’Cheyne records for us the Lord’s dealings with him in a poem entitled Jehovah Tsidkenu.
M'Cheyne here recounts his testimony of salvation: usually we do it in prose, he does it in poetry as it is more expressive of his thoughts and sentiments.
The Lord, taking all initiative in salvation, finds M'Cheyne (like all others) a wayward sinner, encompassed all about with perils and, most of all, the danger of eternal punishment. The Lord first approached him with the sounding of the gospel, but it had no effect; M'Cheyne's understanding and heart were still unopened, and he was not able to appreciate the righteousness wrought out on Calvary. Nothing registered to him.
First through his friends, and apparently later the Lord led him to read for himself the pages of the Sacred Book, both about the Christ of prophecy and the Christ of history - one Christ indeed: Christ predicted and Christ appearing in human flesh. Still, the Golgotha event did not mean anything to M'Cheyne.
The most M'Cheyne felt was a sympathy for Jesus Christ, who was crucified in weakness, and yet the power of that atonement was yet unknown to him. He liked the story and yet could not find any lasting value in it.
God not only induced M'Cheyne to search the Scriptures: He also granted him that "free grace" which, when received, brings about repentance. The Lord made him see the filth and hideousness of his sins, and then there was no other safe place for his soul, except Calvary. There he realized that the sacrifice offered once and for all was all his righteousness that he could appeal to. The terror of eternal perdition vanished; his guilt was removed, and M'Cheyne was given boldness and confidence to call upon the Lord as his righteousness, not wrought in him or by him, but wrought by Another, even Jesus.
God made him see that Christ is indeed the elect sinner's all in all (Philippians 3:3-10).
3 For we are the circumcision, which worship God in the spirit, and rejoice in Christ Jesus, and have no confidence in the flesh. 4 Though I might also have confidence in the flesh. If any other man thinketh that he hath whereof he might trust in the flesh, I more: 5 Circumcised the eighth day, of the stock of Israel, of the tribe of Benjamin, an Hebrew of the Hebrews; as touching the law, a Pharisee; 6 Concerning zeal, persecuting the church; touching the righteousness which is in the law, blameless. 7 But what things were gain to me, those I counted loss for Christ. 8 Yea doubtless, and I count all things but loss for the excellency of the knowledge of Christ Jesus my Lord: for whom I have suffered the loss of all things, and do count them but dung, that I may win Christ, 9 And be found in Him, not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith: 10 That I may know Him, and the power of His resurrection, and the fellowship of His sufferings, being made conformable unto His death
As M'Cheyne moved on in the Christian life, he even was taught to boast in Jehovah Tsidkenu; he was given the joy of assurance in the midst of all temptations and perils. His firm resolve, his whole mindset was to grasp the righteousness of Christ and cling tenaciously to it as his confidence for heaven and eternal blessedness.