If Satan fume and roar against you, whether it be against your bodies by persecution, or inward in your conscience by a spiritual battle, do not be discouraged, as though you were less acceptable in God’s presence, or that Satan might at any time prevail against you. No! Your temptations and storms that arise so suddenly argue and witness that the seed that is sown has fallen on good ground, has begun to take root, and shall, by God’s grace, bring forth fruit abundantly in due season and convenient time. That is what Satan fears; and therefore thus he rages (and shall rage) against you, thinking that if he can repulse you now suddenly in the beginning, that then you will be at all times an easy prey, never able to resist his assaults. But as my hope is good, so shall my prayer be, that you may be so strengthened, that the world and Satan himself may understand and perceive, that God fights your battle.
- John Knox (via 300 Quotations for Preachers from the Reformation)