Perhaps the greatest trial of Saint Paisios of Mount Athos happened when he was still a child
The Saint once said, “From the age of eleven, I read the lives of the Saints.

Fasted and kept vigil older brother would take the books and hide them, but that didn’t stop me. I would just go into the forest and keep reading there.

Later, when Arsenios – the latter Saint Paisios of Mount Athos – was fifteen, a friend of his brother’s named Costas told his brother, “I’ll make him willingly give up all this stuff.” As the Elder related, “He came and explained to me Darwin’s theory of evolution. I was shaken by this, and I said, “I’ll go and pray, and, if Christ is God, He will appear to me so that I’ll believe. “A shadow, a voice—He will show me something.” That’s all I could come up with.

So, I went and began to pray and make prostrations, which I did for hours, but – nothing happened. Finally I stopped in a state of exhaustion. Then something Costas had said came to mind: “I accept that Christ is an important man,” he had told me, “righteous and virtuous, Who was hated out of envy for His virtue and condemned by His countrymen.” I said to myself, “Since that’s how Christ was, even if He was only a man, He deserves my love, obedience, and self-sacrifice. I don’t want paradise – I don’t want anything. It is worth making every sacrifice for the sake of His holiness and kindness.”

“God was waiting to see how I would deal with this temptation. And after this Christ Himself appeared to me in a great light. He was visible from the waist up. He looked on me with tremendous love and said to me, “I am the resurrection, and the life; he that believeth in Me, though he were dead, yet shall he live” (John 11:25). He was holding open the Gospel in His left hand, where the same words were written.”

With this event, the uncertainties that had troubled Arsenios’s young soul were overcome, and in divine grace he was given to know Christ as true God and Savior of the world. He was convinced of the truth of the God-man, not by men or by books, but by the very Lord Himself, who revealed Himself to Arsenios even at his tender age. Now, firmly established in faith, he thought to himself, “Costas, come back now if you want to, and we’ll have a talk.”