Acts 16:30

“And brought them out, etc.] Of the inner prison, to some part of the prison that was more free and open: and said, Sirs, what must I do to be saved? he treats them with great reverence now, and addresses them under a title and character of honour and respect; whom but a few hours ago he despised and abhorred, and perhaps knew no name bad enough for them; he now saw himself lost and perishing, and wanted their instructions, advice, and assistance; and as most persons under first awakenings are, so he was, upon the foot of works; thinking he must do something to procure his salvation, and desires to know what it was he must do, that he might set about it directly; and it may be he had heard…”

“Sirs, what must I do to be saved?--If this question should seem in advance of any light which the jailer could be supposed to possess, let it be considered (1) that the "trembling" which came over him could not have arisen from any fear for the safety of his prisoners, for they were all there; and if it had, he would rather have proceeded to secure them again than leave them, to fall down before Paul and Silas. For the same reason it is plain that his trembling had nothing to do with any account he would have to render to the magistrates. Only one explanation of it can be given--that he had become all at once alarmed about his spiritual state, and that though, a moment before, he was ready…”

“And brought them out - From the prison. Sirs - Greek: κύριοι kurioi, lords - an address of respect; a title usually given to masters or owners of slaves. What must I do to be saved? - Never was a more important question asked than this. It is clear that by the question he did not refer to any danger to which he might be exposed from what had happened. For: (1) The apostles evidently understood him as referring to his eternal salvation, as is manifest from their answer, since to believe on the Lord Jesus Christ would have no effect in saving him from any danger of punishment to which he might be exposed from what had occurred. (2) He could scarcely now consider himself as exposed to…”

“Sirs - He did not style them so the day before. What must I do to be saved? - From the guilt I feel and the vengeance I fear? Undoubtedly God then set his sins in array before him, and convinced him in the clearest and strongest manner that the wrath of God abode upon him. Acts 16:31”

“brought: Act 16:24; Job 34:32; Isa 1:16, Isa 1:17, Isa 58:6, Isa 58:9; Mat 3:8, Mat 5:7; Jam 2:13 Sirs: Act 14:15 what: Act 16:17, Act 2:37, Act 9:6, Act 22:10; Job 25:4; Luk 3:10; Joh 6:27-29 Acts 16:31”