Complex sentence: At 16, he becomes very spiritual: he prayed a lot and even planned to study theology, but he finally sets out to study law, because, apparently, he likes to be the one who is listened to.
Split into simpler sentences: At 16, he becomes very spiritual: he prayed a lot and even planned to study theology. He then sets out to study law, because, apparently, he likes to be the one who is listened to.