Heidelberg Catechism

Question 62. But why cannot our good works be the whole, or part of our righteousness before God?

Answer: Because, that the righteousness, which can be approved of before the tribunal of God, must be absolutely perfect, (a) and in all respects conformable to the divine law; and also, that our best works in this life are all imperfect and defiled with sin. (b)

(a) Gal.3:10 For as many as are of the works of the law are under the curse: for it is written, Cursed is every one that continueth not in all things which are written in the book of the law to do them. Deut.27:26 Cursed be he that confirmeth not all the words of this law to do them. And all the people shall say, Amen. (b) Isa.64:6 But we are all as an unclean thing, and all our righteousnesses are as filthy rags; and we all do fade as a leaf; and our iniquities, like the wind, have taken us away.

Question 63. What! do not our good works merit, which yet God will reward in this and in a future life?

Answer: This reward is not of merit, but of grace. (a)

(a) Luke 17:10 So likewise ye, when ye shall have done all those things which are commanded you, say, We are unprofitable servants: we have done that which was our duty to do.

Question 64. But does not this doctrine make men careless and profane?

Answer: By no means: for it is impossible that those, who are implanted into Christ by a true faith, should not bring forth fruits of thankfulness. (a)

(a) Matt.7:18 A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit. John 15:5 I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.