Whoever speaks peace to himself upon any one account, and at the same time hath another evil of no less importance lying upon his spirit, about which he hath had no dealing with God, that man cries “Peace” when there is none.
A little to explain my meaning: A man hath neglected a duty again and again, perhaps, when in all righteousness it was due from him; his conscience is perplexed, his soul wounded, he hath no quiet in his bones by reason of his sin; he applies himself for healing, and finds peace. Yet, in the meantime, perhaps, worldliness, or pride, or some other folly, wherewith the Spirit of God is exceedingly grieved, may lie in the bosom of that man, and they neither disturb him nor he them. Let not that man think that any of his peace is from God. Then shall it be well with men, when they have an equal respect to all God’s commandments. God will justify us from our sins, but he will not justify the least sin in us: “He is a God of purer eyes than to behold iniquity.”
– John Owen –
from The Mortification of Sin in Believers, volume 6 of Works, page 77