And as many reserve the dregs of their lives, their old age, to offer up their souls to God, so they reserve the dregs of the day, their sleeping time, for the offering up their service to him. How many grudge to spend their best time in the serving the will of God, and reserve for him the sickly and rheumatic part of their lives; the remainder of that which the devil and their own lusts have fed upon… When by age men are weary of their own bodies, they would present them to God; yet grudgingly, as if a tired body were too good for him, snuffing at the command for service. God calls for our best, and we give him the worst (italics added).
-Stephen Charnock, The Existence and Attributes of God (vol. 1), p. 113-14
What we call service to God is done naturally much against our wills; it is not a delightful food, but a bitter potion; we are rather haled, than run to it. There is a contradiction of sin within us against our service… Our hearts are unwieldy to any spiritual service of God; we are fain to use violence with them sometimes… Man’s nature, being contrary to holiness, hath an aversion to any act of homage to God, because holiness must at least be pretended; now as men are against the truth of holiness, because it is unsuitable to them, so they are not friends to those duties which require it, and for some space divert them from their beloved lusts. The word of the Lord is a yoke, prayer a drudgery, obedience a strange element.
– Stephen Charnock, The Existence and Attributes of God (Vol. 1), p. 112