From the Living of Saint Pachomius the Great.
But guided by the holy Spirit, he thought for a while, then spurned this vision of the enemy.
Letter 414. Question: "If a sinner should acquire certain visions, should that person not believe at all that these are from God?"
Response: When this happens to a sinner, it is clear that it has from the demons, in order to deceive the wretched soul of that person into destruction. Therefore, one should never believe in these, but one should rather cоmе to know one's own sins and weaknesses, in order always to lead a life in fear and trembling.
Letter 415. Question: "So should one also turn away from these visions, even when they appear in the Form of the Master Christ?"
Response: It is especially then that we should turn away from and anathematize their wickedness and deceit even more so. Brother, never be deceived, therefore, by such demonic assurance. For divine visions certainly occur to the saints, but they are always preceded by calm, peace, and joy in their hearts. Indeed, the saints are always aware of the truth and regard themselves as being unworthy [of such visions]. How much more, then, should sinners never believe these visions, when they are aware of their own unworthiness?