Thomas a Kempis, The Imitation of Christ Ch 3

"Happy is he whom truth by itself doth teach, not by figures and words that pass away; but as it is in itself (Psalm 94:12).

Our own opinion and our own sense do often deceive us, and they discern but little...It is folly to neglect the things that are profitable and necessary, and give our minds to that which is curious and hurtful: we have eyes and see not.

...Who hinders and troubles thee more than the unfortified affections of thine own heart?

...This ought to be our endeavor, to conquer ourselves, and daily wax stronger and to make a further growth in holiness. All perfection in this life hath some imperfection mixed with it; and no knowledge of ours is without some darkness."

Devotional- Thomas a Kempis

Vanity therefore it is, to seek after perishing riches, and to trust in them.

It is vanity to hunt after honors, and to climb to high degree.

It is vanity to follow the desires of the flesh, and to labour for that which thou must afterward suffer more grievous punishment.

Vanity it is, to wish to live long, and to be careless to live well.

..."The eye is not satisfied with seeing, not the ear filled with hearing" Eccles. 1:8

Endeavor therefore to withdraw thy heart from the love of visible things,
and turn thyself to in invisible.

For they that follow their lusts, do stain their own consciences...