Verse 21. Meantime I do not make void - In seeking to be justified by my own works. The grace of God - The free love of God in Christ Jesus. But they do, who seek justification by the law. For if righteousness is by the law - If men might be justified by their obedience to the law, moral or ceremonial. Then Christ died in vain - Without any necessity for it, since men might have been saved without his death; might by their own obedience have been both discharged from condemnation, and entitled to eternal life.