Deuteronomium 20:19

Verse 19. When the regenerate will has great difficulty in overcoming the arguments of falses that oppose truth (either in the man's own mind or in the minds of others), and endures severe temptations because of them, great care must be taken not to destroy the knowledges or perceptions of truth which support the false doctrine (as far as they are genuine) by the dogmatic assertion of truth; for these perceptions or knowledges may be conducive to the regenerate life; you shall not obliterate these perceptions, for these very perceptions, which form the soul's rational perception of truth, are the very means by which the false doctrines may be eventually overcome in the soul (for, O man, the tree of the field is to be employed in the siege, marginal reading).