Malbim: Mitzvah is a commander forcing the commanded to do his order, e.g. a father to his son, and a master to his slave. It is attributed to the father, for he forces [his son] to guard his commands, even if they oppose the nature of his heart.

Malbim: Torah is teachings, e.g. Emunos, mindsets and Musarim. After he will guard his father's command, automatically he will not abandon his mother's Torah, for the nature of man's Nefesh is to be drawn after Torah, unless he despises a Mitzvah. Then he abandons Torah and contradicts fundamentals of Emunah, in order to cast off the yoke of Mitzvos. One who guards Mitzvah will not abandon Torah.