"This subject [justification] suggests grounds of trial. — Are you justified or not? I do not ask if you justify yourselves, or if men justify you; but does God justify you? If you are guilty but of one sin, and have not repented, you are as certainly condemned as if you had been guilty of ten thousand. The chains of natural corruption with which you are girded declare you to be still under condemnation. Now, have you seen and felt yourselves in a state of condemnation?
"Justification is a judiciary sentence, and before you can expect it, you must appear in court, and answer to your libel. Do you see your want of a perfect righteousness, the insufficiency of your own performances, and at the same time, the gift, suitableness, and sufficiency of the righteousness of Jesus Christ? Do you trust cordially in Christ as Jehovah your Righteousness? And are you humbled for your unbelief? Have you ever been grieved and troubled for the legal propensity of your heart? Is your self-righteous temper a burden, and a sore grievance to you? If so, it is a favourable sign. Do you rely on Christ's righteousness for all your title to eternal life? Believe more, trust more; for they who believe are justified from all things, etc.
"Let secure sinners consider, that every sermon addressed to them is a summons put into their hands, to answer for their innumerable sins at the bar of that omniscient God whose eyes are as a flame of fire. What consternation will seize you, O condemned and impenitent sinner, when you shall see an infinitely just Judge upon his great white throne; when you shall find a strict law before you, and an accusing conscience within! Like Shimei you have broken through your rules of confinement, and are men of death. Be persuaded that you cannot be justified but on the ground of a perfect righteousness; and you have no such righteousness of your own. Rely, then, for the justification of life on the surety-righteousness of the Lord Jesus, freely offered in the Gospel to you. Renew frequently your actings of faith on Him as your righteousness and strength, and glory in his finished work."John Colquhoun. Sermons, Chiefly on Doctrinal Subjects - Justification, Sermon IX, 162-163
*Earlier posts with excerpts from Colquhoun's Justification Sermon are here and here.