When the soul in the course of its behaviour walks in the way of faith, this improves it much.
When it then turns towards the means of knowledge, it becomes alienated to faith at once.
And it is removed from that intelligible force of faith which reveals itself by different acts of help in the serene soul that simply, without inquiry, uses all that belongs to it.
The soul that has once, in faith, entrusted itself unto God and, under many temptations, has received the taste of faith’s help, no longer thinks of itself, but is made speechless by ecstasy and silence, nor is it allowed to return unto the means of its knowledge or to make use of them, lest it also be bereft, on the contrary, of the divine care which visits it incessantly and provides for it and clings to it everywhere.
For the soul would consider it as a despicable thought to deem itself sufficient to guide itself by the power of its knowledge.
For those in whose hearts the light of faith has dawned, do not venture to pray in their own behalf, they do not even venture to ask God: Give us this, or: Take from us that, nor dare they think of themselves in any way.
For by the initiated eyes of their faith they always see the paternal care which protects them on the part of that Father whose strong and immeasurable love surpasses the love of all fleshly fathers and who has power to supply us with all things above what we ask and think.
[…] Faith…requires a serene and simple mind, far from any cunning or need of means.
Behold, how knowledge and faith are each other’s opposites. The mansion of faith is a childlike mind and a pure heart. For in the purity of their heart people have praised God. For ‘except ye be converted and become as little children’ (Matt. 18:3) and so on.
Knowledge, however is the persecutor and opposite of these two. Knowledge adheres to the domain of nature, in all its ways. Faith makes its course above nature.
Knowledge does not admit unto itself anything which is in disharmony with nature, not even for the sake of trial, but it lets these things dwell at a distance.
Faith on the other hand orders with authority and says: Thou shall tread upon the serpent and the lion: the young lion and the dragon shalt thou trample under feet (Psalm 90:13).
Isaac the Syrian (c. 630-c. 700): Mystic Treatises, 51, in Mystical Treatises of Isaac of Nineveh, trans. A.J. Wensinck, pp. 242-243.