(3.) They very readily directed him what he must do, v. 31. They were always ready to answer such enquiries; though they are cold, and sore, and sleepy, they do not adjourn this cause to a more convenient time and place, do not bid him come to them the next sabbath at their meeting-place by the river side, and they will tell him, but they strike while the iron is hot, take him now when he is in a good mind, lest the conviction should wear off. Now that God begins to work, it is time for them to set in as workers together with God. They do not upbraid him with his rude and ill carriage towards them, and his going beyond his warrant; all this is forgiven and forgotten, and they are as glad to show him the way to heaven as the best friend they have. They did not triumph over him, though he trembled; they gave him the same directions they did to others, Believe in the Lord Jesus Christ. One would think they should have said, "Repent of thy abusing us, in the first place." No, that is overlooked and easily passed by, if he will but believe in Christ. This is an example to ministers to encourage penitents, to meet those that are coming to Christ and take them by the hand, not to be hard upon any for unkindness done to them, but to seek Christ's honour more than their own. Here is the sum of the whole gospel, the covenant of grace in a few words: Believe in the Lord Jesus Christ, and thou shalt be saved, and thy house. Here is, [1.] The happiness promised: "Thou shalt be saved; not only rescued from eternal ruin, but brought to eternal life and blessedness. Though thou art a poor man, an under-jailer or turnkey, mean and of low condition in the world, yet this shall be no bar to thy salvation. Though a great sinner, though a persecutor, yet thy heinous transgressions shall be all forgiven through the merits of Christ; and thy hard embittered heart shall be softened and sweetened by the grace of Christ, and thus thou shalt neither die for thy crime nor die of thy disease." [2.] The condition required: Believe in the Lord Jesus Christ. We must admit the record that God hath given in his gospel concerning his Son, and assent to it as faithful, and well worthy of all acceptation. We must approve the method God has taken of reconciling the world to himself by a Mediator; and accept of Christ as he is offered to us, and give up ourselves to be ruled and taught and saved by him. This is the only way and a sure way to salvation. No other way of salvation than by Christ, and no other way of our being saved by Christ than by believing in him; and no danger of coming short if we take this way, for it is the way that God has appointed, and he is faithful that has promised. It is the gospel that is to be preached to every creature, He that believes shall be saved. [3.] The extension of this to his family: Thou shalt be saved, and thy house; that is, "God will be in Christ a God to thee and to thy seed, as he was to Abraham. Believe, and salvation shall come to thy house, as Luke 19 9. Those of thy house that are infants shall be admitted into the visible church with thee, and thereby put into a fair way for salvation; those that are grown up shall have the means of salvation brought to them, and, be they ever so many, let them believe in Jesus Christ and they shall be saved; they are all welcome to Christ upon the same terms."

Matthew Henry Commentary on the Whole Bible (Concise) (Matthew Henry)

Verses 25-34 The consolations of God to his suffering servants are neither few nor small. How much more happy are true Christians than their prosperous enemies! As in the dark, so out of the depths, we may cry unto God. No place, no time is amiss for prayer, if the heart be lifted up to God. No trouble, however grievous, should hinder us from praise. Christianity proves itself to be of God, in that it obliges us to be just to our own lives. Paul cried aloud to make the jailer hear, and to make him heed, saying, Do thyself no harm. All the cautions of the word of God against sin, and all appearances of it, and approaches to it, have this tendency. Man, woman, do not ruin thyself; hurt not thyself, and then none else can hurt thee; do not sin, for nothing but that can hurt thee. Even as to the body, we are cautioned against the sins which do harm to that. Converting grace changes people's language of and to good people and good ministers. How serious the jailer's inquiry! His salvation becomes his great concern; that lies nearest his heart, which before was furthest from his thoughts. It is his own precious soul that he is concerned about. Those who are thoroughly convinced of sin, and truly concerned about their salvation, will give themselves up to Christ. Here is the sum of the whole gospel, the covenant of grace in a few words; Believe in the Lord Jesus Christ, and thou shalt be saved, and thy house. The Lord so blessed the word, that the jailer was at once softened and humbled. He treated them with kindness and compassion, and, professing faith in Christ, was baptized in that name, with his family. The Spirit of grace worked such a strong faith in them, as did away further doubt; and Paul and Silas knew by the Spirit, that a work of God was wrought in them. When…