Anything allowed in the heart which is contrary to the will of God, let it seem ever so insignificant, or be ever so deeply hidden, will cause us to fall before our enemies. Any root of bitterness cherished towards another, any self-seeking, any harsh judgments indulged in, any slackness in obeying the voice of the Lord, any doubtful habits or surroundings, any one of these things will effectually cripple and paralyze our spiritual life. I believe our blessed Guide, the indwelling Holy Spirit, is always secretly discovering these things to us by continual little twinges and pangs of conscience, so that we are left without excuse.
~ Hannah Whitall Smith