Unlike the other accounts of individual conversions in the book of Acts, we aren’t given any indication that the Philippian jailer believed in God or was even a moral human being before his conversion in Acts 16. Regardless of his prior beliefs (or non-beliefs) and lifestyle choices, he observed the effects of the miraculous earthquake, listened to Paul and Silas praying and singing while locked in his prison, and understood that some action was required on his part “to be saved.” Once Paul displayed compassion and mercy towards him, the jailer asked what he needed to do. He was instructed to believe because that was the first step, and Paul subsequently preached the gospel to him so that he might understand what he needed to believe. The jailer did not rejoice until after he had tended to the wounds inflicted on Paul and Silas (demonstrating repentance) and was baptized the “same hour of the night.” Only then did he rejoice because only then had he been fully converted.
Speak where the Bible speaks.