This will appear, if we consider, that the choice of an end implies the choice of it, not for no reason, but for a reason, and for its own intrinsic value, or because the mind prizes it on its own account. But moral agents are so constituted, that they cannot regard misery as intrinsically valuable. They cannot, therefore, choose it as an ultimate end, nor prize it on its own account. Disobedience to moral law cannot consist in the constitution of soul or body. The law does not command us to have a certain constitution, nor forbid us to have the constitution with which we came into being.
Moral agents are necessarily active.
That is, they cannot exist as moral agents without choice. They must, by a law of necessity, choose either in accordance with, or in opposition to, the law of God. They are free to choose in either direction, but they are not free to abstain from choice altogether. Choose they must. The possession of free will, and the perception of opposing objects of choice, either exciting desire, or developing the rational affirmation of obligation to choose, render choice one way or the other inevitable.