It is good to find opportunities to exercise self-control, for example by learning to endure hunger, thirst, heat, cold or fatigue. This is not to say you should constantly live in a state of deprivation or become yogis.
No, of course not. But look how people generally rush to find something to eat or drink the moment they are hungry or thirsty, and if they do not find it immediately, they complain, grumble and become angry.
Observe yourselves and you will see that in all kinds of situations, you cannot bear being unable to satisfy your desires and even your petty whims at once. So how are you going to control your anger, your jealousy, your hatred or your sexual desires? You may well know that it is best to control yourself and you may have tried to do so, but if you haven’t learned to exercise your willpower, you will not succeed.