To lead a discouraged people to the Holy War is as difficult as for Xerxes’ commanders to conduct the Persian troops to battle against the Greeks, The vassals of the great king were driven to the conflict by whips and sticks, for they were afraid to fight: do you wonder that they were defeated? A Church that needs constant exhorting and compelling accomplishes nothing.

The Greeks had no need of blows and threats, for each man was a lion, and courted the encounter, however great the odds against him. Each Spartan fought con amore (with love); he was never more at home than when contending for the altars and for the hearths of his country.

We want Christian men of this same sort, who have faith in their principles, faith in the doctrines of grace, faith in God the Father, God the Son, and God the Holy Ghost; and who therefore contend earnestly for the faith in these days when piety is mocked at from the pulpit, and the gospel is sneered at by professional preachers. We need men who love the truth, to whom it is dear as their lives; men into whose hearts the old doctrine is burned by the hand of God’s Spirit through a deep experience of its necessity and of its power. We need no more of those who will parrot what they are taught, but we want men who will speak what they know. Oh, for a troop of men like John Knox, heroes of the martyr and covenanter stock! Then would Jehovah of hosts have a people to serve Him who would be strong in the Lord and in the power of His might.

—Charles H. Spurgeon,
The Metropolitan Tabernacle, (Banner of Truth Trust, 1876), Hag 2:4–5.