The Lord stood with him strengthening him, not to escape from the prison (even if he could and had done that on different occasions- Acts 5:18-19, 12:7-10)
But he strengthened him so others would hear the gospel message preached; even if they congregated to watch Paul being torn to shreds by a lion, Jesus was still concerned about their souls and giving them an opportunity to believe, 2 Timothy 4:17. He was the one who told Paul:
“To open their eyes, and to turn them from darkness to light, and from the power of Satan unto God…” Acts 26:18
He knew that their hatred for him was due to the wicked influence of satan (2 Corinthians 4:4). How kind he truly is, and Paul being led by and working with the Spirit (2 Corinthians 6:1), knowing this strengthening of the Spirit:
“That he would grant you, according to the riches of his glory, to be strengthened with might by his Spirit in the inner man;” Ephesians 3:16
was clear on what he ought to do; they wanted him dead, but he wanted them saved and why no? By grace he was delivered from damnation while he was wishing death on other disciples: Acts 22:4.

Bible Reading Plan: Psalms 12 and Deuteronomy 33