This chapter gives the church and people of God reason to expect comfortable times and certain salvation, though they had many enemies. They are directed to look to Abraham and Sarah, signified by the rock and hole of the pit, and observe how he was called alone, blessed and increased; which should be improved as an argument to strengthen their faith, that God could and would bless and increase his church, though in a low estate, and bring it into a flourishing one, Isa 51:1-3. They are assured of the publication of the Gospel, expressed by the law, doctrine, and judgment of the Lord; by which means the righteousness and salvation of Christ should be brought nigh to them, as the object of their trust and confidence, Isa 51:4,5, and also of the perpetuity of his righteousness and salvation, when the heavens, and the earth, and the inhabitants of it, should decay, even their revilers and persecutors, and therefore they need not fear their reproaches and revilings, Isa 51:6-8, upon which follows a prayer of faith, that the Lord would exert his power as in former times, when he destroyed the Egyptians, and dried up the Red sea for Israel to pass through, the ransomed of the Lord; from whence it might be concluded, that the redeemed of the Lord would be brought into a very comfortable condition again, Isa 51:9-11 wherefore they had no reason to be afraid of men, since the Lord, the Maker of heaven and earth, would deliver, comfort, and establish them, of which he assured them by his prophet, Isa 51:12-16, and though Jerusalem and her sons were, or would be, in a very distressed condition, through the sword and famine, which is described, Isa 51:17-20, yet they should be delivered out of it, and their persecutors should be brought into the same, Isa 51:21-23.