The Apostle Paul writes in Rom. 1:16 that the gospel is the power of God unto salvation for everyone who believes.  This power of God is on full display in Acts 9 and it will cause us to consider: How much do we believe in the saving power of God?  This will be expressed initially in how we view our own salvation.  In our Ephesians home Bible study, we recently covered Eph. 2:1 And you were dead in the trespasses and sins 2 in which you once walked, following the course of this world, following the prince of the power of the air, the spirit that is now at work in the sons of disobedience— 3 among whom we all once lived in the passions of our flesh, carrying out the desires of the body and the mind, and were by nature children of wrath, like the rest of mankind (ESV).
This description fits every single person to ever live, so what kind of power would it take to transform that kind of person?  According to the end of ch.1, it’s the same power that raised Christ from the dead and exalted him to God’s right hand.  That’s what kind of power that is at play when God makes sinners alive a few verses later in Eph. 2.  Every Christian had to be given that divine power in order to be saved.
Secondly, our belief in the gospel as the power of God will be manifested in our persistent prayers for unbelievers.  How quickly do we give up praying for someone when they show resistance or indifference to the gospel?  How about when they turn to a life of blatant sin?  Or, as it relates to the really wicked people we know, perhaps we don’t really pray for them at all because they are so far from God, what’s the point?  This conversion of Saul in Acts 9 serves as a stiff rebuke to those faulty mindsets.