Adam Clarke's Commentary on the Bible

Verse 22 (Romans 14:22)

Hast thou faith? - The term faith seems to signify in this place a full persuasion in a man's mind that he is right, that what he does is lawful, and has the approbation of God and his conscience. Dr. Taylor has a judicious note on this passage. "There is no necessity," says he, " for reading the first clause interrogatively; and it seems to be more agreeable to the structure of the Greek to render it, Thou hast faith; as if he had said: 'I own thou hast a right persuasion.' Farther, there is an anadiplosis in εχεις , and εχε the first simply signifies thou hast, the latter, hold fast. Thou hast a right persuasion concerning thy Christian liberty; and I advise thee to hold that persuasion steadfastly, with respect to thyself in the sight of God. Εχω have, has frequently this emphatical signification. See Matthew 25:29 , etc."

Happy is he that condemneth not, etc. - That man only can enjoy peace of conscience who acts according to the full persuasion which God has given him of the lawfulness of his conduct: whereas he must be miserable who allows himself in the practice of any thing for which his conscience upbraids and accuses him. This is a most excellent maxim, and every genuine Christian should be careful to try every part of his conduct by it. If a man have not peace in his own bosom, he cannot be happy; and no man can have peace who sins against his conscience. If a man's passions or appetite allow or instigate him to a particular thing, let him take good heed that his conscience approve what his passions allow, and that he live not the subject of continual self-condemnation and reproach. Even the man who has the too scrupulous conscience had better, in such matters as are in question, obey its erroneous dictates than violate this moral feeling, and live only to condemn the actions he is constantly performing.

- Adam Clarke's Commentary on the Bible