St Peter of Damaskos | God possesses a perfect knowledge of all these things...

God possesses a perfect knowledge of all these things, just as He knows the past, the present and the future; and they are known to some extent by him, who through grace, has learned from God about His works, and who through this grace has been enabled to realize in himself that which is according to God’s image and likeness (cf. Gen. 1:26).

But if someone claims that, simply by hearing about these things, he knows them as he should, he is a liar. Man’s intellect can never rise to heaven without God as a guide; and it cannot speak of what it has not seen, but must first ascend and see it.

On the level of hearsay, you should speak only of things that you have learnt from the Scriptures, and then with circumspection, confessing your faith in the Father of the Logos, as St Basil the Great puts it, and not imagining that through hearsay you possess spiritual knowledge; for that is to be worse than ignorant.

As St Maximos has said, 
‘To think that one knows prevents one from advancing in knowledge.’

St John Chrysostom points out that there is an ignorance which is praiseworthy: it consists in knowing consciously that one knows nothing.

In addition, there is a form of ignorance that is worse than any other: not to know that one does not know. Similarly, there is a knowledge that is falsely so called, which occurs when, as St Paul says, one thinks that one knows but does not know (cf. 1 Cor. 8:2).

St Peter of Damaskos