Usually the impression is given that he was a rough and wild man. Nevertheless, such a suggestion is open to question. It is very unlikely that the Roman authorities would have used such an undisciplined person in this important position.
It is clear from the passage that he was used to obeying orders and his treatment of Paul and Silas was according to the instructions he received. In a sense, this man was a government employee, with all the privileges that came with his role. So he would have enjoyed a measure of security.
Whatever may have been these securities, he found himself in a situation where they could not do him any good. In a moment he discovered the fragility of his situation. He knew that he was accountable for the prisoners with his own life, and suicide seemed the only option. All his hopes for the future had been dashed.
In these two factors, the jailor is a picture of many of us. We have reasonably secure positions in society through our work and station in life. Then something happens that shows to us that these things cannot really help us when troubles come.
Sometimes God has to remove things from us before we will listen to him. He does not do this with everyone; for example, he did not bring any problems into the life of Lydia. With the young girl, he removed her from various evils that were afflicting her. It was different with the jailor. God knows what it will take to bring a person to repentance.