"Beginners in the spiritual life are apt to become very diligent in their exercises, (prayers, Bible reading, memorization, church service etc.)
The great danger for them will be to become satisfied with their religious works and with themselves. It is easy for them to develop a kind of secret pride, which is the first of the seven "Capital" sins.
Such persons become too spiritual. They like to speak of "spiritual things" all the time.
They become content with their growth.
They would prefer to teach rather than to be taught.
They condemn others who are not as spiritual as they are. They are like the Pharisee who boasted in himself and despised the publican who was not as spiritual as he.
The devil will often inflame their fervor so that their pride will grow even greater.
The devil knows that all of their works and virtues will become valueless and if unchecked, will become vices. For they begin to do these spiritual exercises to be esteemed by others. They want others to realize how spiritual they are.
They will also begin to fear confession to another for it would ruin their image. So they soften their sins when they make confession in order to make them appear less imperfect.
They will beg God to take away their imperfections, but they do this only because they want to find inner peace and not for God's sake. They do not realize that if God were to take away their imperfections from them, they would probably become prouder and more presumptuous still.
But those who are at this time moving in God's way will counter this pride with humility.
They will learn to think very little of themselves and their religious works.
Instead, they will focus on how great and how deserving God is and how little it is that they can do for Him. The Spirit of God dwells in such persons, urging them to keep their treasures secretly within themselves."
John of the cross. The Dark Night of the Soul.