Righteousness shall go before him; and shall set us in the way of his steps. Righteousness shall go before him - Perhaps this verse may receive its best solution from Romans 3:25 : "Whom God hath set for a propitiation through faith in his blood, to declare his Righteousness for the remission of sins that are past." This term the apostle uses to point out God's method of justifying or saving mankind. And this, in the preaching of the pure Gospel, is ever going before to point out the Lord Jesus, and the redemption that is in his blood. And thus going before him, the sinner, who feels his need of salvation, is Set - in the way of his steps; as Bartimeus sat by the way-side begging, by which way Jesus walked; and when he came where he was, heard his prayer, and restored him his sight. Or, righteousness - the pure and holy law of God, must be proclaimed as broken by sinners, and calling aloud for vengeance, before they can see and feel their need of Christ crucified. By the preaching of the law they are prepared to receive the grace of the Gospel.
Commentary on the Bible, by Adam Clarke [1831].