Not antecedent but consequent
The case is not therefore as you suppose, that men were once more obliged to obey God, or to work the works of his law than they are now. This is a supposition you cannot make good. But, we should have been obliged, if we had been under the covenant of works, to have done those works antecedent to our acceptance. Whereas now all good works, though as necessary as ever, are not antecedent to our acceptance but consequent upon it. Therefore the nature of the covenant of grace, gives you no ground, no encouragement at all, to set aside any instance or degree of obedience, any part or measure of holiness.
1771 text
4. The case is not therefore as you suppose, that men were once more obliged to obey God, or to work the works of his law than they are now. This is a supposition you cannot make good. But, we should have been obliged, if we had been under the covenant of works, to have done those works antecedent to our acceptance. Whereas now all good works, tho’ as necessary as ever, are not antecedent to our acceptance but consequent upon it. Therefore the nature of the covenant of grace, gives you no ground, no encouragement at all, to set aside any instance or degree of obedience, any part or measure of holiness.