John Calvin Commentary Hebrews 13:18

"Pray for us: for we are persuaded that we have a good conscience, desiring to live honorably in all things." — Hebrews 13:18 (ASV)

For we trust, and so on. After commending himself to their prayers, in order to encourage them to pray, he declares that he had a good conscience.

Though our prayers should indeed embrace the whole world, as love does from which they flow, yet it is right and fitting that we should be especially concerned for godly and holy men, whose integrity and other marks of excellence have become known to us. To this end, then, he mentions the integrity of his own conscience; that is, so that he might more effectively move them to feel concern for him.

By saying, ‘I am persuaded,’ or ‘I trust,’ he thus partly shows his modesty and partly his confidence. In all, may be applied to things as well as to people, and so I leave it undecided.