[F]or things that are not so [i.e., not fundamental], we are to weigh them in two balances, in the balance of analogy, and in the balance of scandal: we must hold them so, as may be analogal, proportionable, agreeable to the articles of our faith, and we must hold them so, as our brother be not justly offended, nor scandalized by them; we must weigh them with faith, for our own strength, and we must weigh them with charity, for others' weakness.
Source: wiktionary