Parshas Shoftim

When a new king is appointed there's a mitzva for him to write himself a new Sefer Torah. Just like everyone else, there is a mitzva for him to own a Sefer Torah, in addition to this he is to write a new one that he is to carry with him, at all times. The meforshim explain that this is the source of our minhag that a chosson gets an aliyah to the Torah the week before and the week after his wedding. The significance of this is that while a king has a upbringing that was vital in forming the person that he is, at the same time he has to realize that only he himself can form his life. He has a Sefer Torah and a rich mesorah handed down from his father and the previous generations. His new Sefer Torah- the one that he is to keep close at all times- is there to ingrain in him that all that was handed down to him by the previous generations is just a backdrop to which to base his decisions that he'll make on his own to which he himself will be responsible for. We try to teach the same lesson to a chosson, to take everything he was taught and experienced in his parents house along with him, but to realize that he's beginning a new stage in life and it's up to him to make sure it's an upstanding Torahdik home.
Thanks to my Father-in-law for this lesson.