A fruit listed by Paul in Galatians 5:22 is self control. Before one is indwelled with the Holy Spirit, there is a facade of self-control. Being fallen in nature, totally depraved, we pursue sin, we seek ways to get away with sin.
Our desires in a fallen nature will only have an accountability to our fellow man, not to God, so our self-control will only encompass this. It is easy to deceive man, but not God. We might believe we have self-control, but in our thoughts, yes thoughts of which God knows intimately, our self-control is non-existent. We might not proceed to the sinful action, but we thought about doing it, thus we sinned.
When indwelled by the Spirit, self-control actually becomes realized. Now it is not only your actions which are restrained but the THOUGHTS on those actions have changed. Your desire for sin has a disdain now, so you seek the opposite which is holiness. Your thoughts coincide. Thus why it is always perplexing to me when a professed Christian man will say he is still addicted to porn or became addicted to porn for example. I would say he was deceived, and most likely not a Christian because the Holy Spirit would have changed that desire.
Now I am not saying self-control comes upon you in a perfect manner, like a lightswitch and BOOM when you are born-again, you will have perfect control. No! But this grows like a seed! The constant conviction in thoughts, words, deeds, actions, an inaction is felt by your core, and that is the indwelling Holy Spirit who is growing your fruit of self-control.
Lastly, a form of self-control in a fallen state is also under God’s sovereign hand! He is restraining evil actions, and the evils of a fallen heart as well. If not for that restraint, the evils of the world would be on a level never witnessed! So we must always thank God for self-control, it truly IS A FRUIT OF THE SPIRIT!