II Corinthians 11:3

I fear, lest by any means, as the serpent beguiled Eve through his subtlety, so your minds should be corrupted from the simplicity that is in Christ.

My brethren, be strong in the Lord, and in the power of his might. Put on the whole armour of God, that ye may be able to stand against the wiles of the devil.

Simplicity is the secret of seeing things clearly. A saint does not think clearly for a long while, but a saint ought to see clearly without any difficulty.

You cannot think a spiritual muddle clear, you have to obey it clear. In intellectual matters you can think things out, but in spiritual matters you will think yourself into cotton wool.