of the will itself, or of the affections, (which are only certain modes of
Natural Inability, arising from the want of natural capacity, or external hindrance, (which alone is properly called Inability,) without doubt wholly excuses, or makes a thing improperly the matter of Command. If men are excused from doing or acting any good thing, supposed to be commanded, it must be through some defect or obstacle that is not in the Will itself, but either in the capacity of understanding, or body, or outward circumstances.-- Here two or three things may be observed, 1. As to spiritual acts, or any good thing in the state or imminent acts of the will itself, or of the affections, (which are only certain modes of the exercise of the Will,) if persons are justly excused, it must be through want of capacity in the natural faculty of understanding. Thus the same spiritual duties, or holy affections and exercises of heart, cannot be required of men, as may be of angels; the capacity of understanding being so much inferior. So men cannot be required to love those amiable persons, whom they have had no opportunity to see, or hear of, or know in any way agreeable to the natural state and capacity of the human understanding. But the insufficiency of motives will not excuse; unless their being insufficient arises not from the moral state of the Will or inclination itself, but from the state of the natural understanding. The great kindness and generosity of another may be a motive insufficient to excite gratitude in the person that receives the kindness, through his vile and ungrateful temper: in this case, the insufficiency of the motive arises from the state of the Will or inclination of heart, and does not at all excuse. But if this generosity is not sufficient to excite gratitude, being unknown, there being no means of information adequate to the state and measure of the person's faculties, this insufficiency is attended with a natural Inability, which entirely excuses it.
2. As to such motions of body, or exercises and alterations of mind, which do not consist in the iniminent acts or state of the Will itself --