His first devotional work, _The Handbook of the Christian Knight_, perfectly sets forth his program of spiritual, as opposed to formal, Christianity.

[Sidenote: _Enchiridion Militis Christiani_, 1503] It all turns upon the distinction between the inner and the outer man, the moral and the sensual.

True service of Christ is purity of heart and love, not the invocation of saints, fasting and indulgences.
In _The Praise of Folly_ Erasmus mildly rebukes the foibles of men.
[Sidenote: 1511] There never was kindlier satire, free from the savage scorn of Crotus and Hutten, and from the didactic scolding of Sebastian Brant, whose _Ship of Fools_ [Sidenote: 1494] was one of the author's models.

Folly is made quite amiable, the source not only of some things that are amiss but also of much harmless enjoyment.

The besetting silliness of every class is exposed: of the man of pleasure, of the man of business, of women and of husbands, of the writer and of the pedant.