“To make a man altogether a Christian, there must be light in the head and heat in the heart, knowledge in the understanding and zeal in the affections. Some have zeal and no knowledge – that is blind devotion. Some have knowledge and no zeal- that is fruitless speculation. But where knowledge is joined with zeal, that makes a true Christian.”
— Matthew Mead
“Zeal is a good thing, but like the horse without a bit, it becomes useless and even dangerous. Knowledge is the bridle in the mouth of zeal. Zeal is like fire which may burn the house which it was intended to warm unless it is carefully governed. There must be knowledge in zeal.”
— C. H. Spurgeon
Romans 10:2-3 For I bear them record that they have a zeal of God, but not according to knowledge. For they being ignorant of God’s righteousness, and going about to establish their own righteousness, have not submitted themselves unto the righteousness of God.