The adversary will not sleep. God's saints noted that he operates on those who are just beginning in two ways:

The adversary will not sleep. God's saints noted that he operates on those who are just beginning in two ways:

 Some the enemy attacks with all his force and swiftness from the very start, and so such beginners are lost.The adversary does this to frighten the neophyte and to make him give up his good intentions and return to his careless and inattentive life.

 On the other hand, with others, he does not disturb them at all and does not put up any opposition. Those who do not encounter inward or outward impediments and who see that everything is going smoothly begin to fantasize that this is the way things are, and they suppose they have driven out all adversaries, who are unable to show themselves. As soon as such thoughts have settled in, the adversary immediately enters and begins fabricating vainglorious dreams from which are born self-conceit, the falling away from God's help, and the cessation of searching and striving after this help. The result of this is deprivation. As soon as matters have reached this point, the adversary begins operating tyrannically to stir up evil inside and strong antagonism from outside, and the poor conceited person falls. Such instances are not rare. 

(St. Theophan the Recluse, The Spiritual Life and How to be Attuned to It)