Certain faithless men took it in hand to test his grace. Day and night, they shadowed the brothers to find out where their food was coming from, for every day they saw it ready, and that after taking what sufficed them, these slaves of God took no thought for the morrow, but gave it in abundance to the poor. Through the Holy Spirit, the blessed one knew of their investigation, and at a time when none had knocked upon their door, said to one of his followers, "Go, and let in what the Lord has sent us." And before the brother got there, a man in white came knocking. The brother opened it to find a basket full of fresh-baked bread, still warm—but the angel of God who had knocked so urgently was nowhere to be seen, leaving a man standing there with the bread. "Who sent you?" the brother asked when he came in. The man responded, "I was taking my loaves out of the oven when a man of giant size appeared beside me, robed in white, and fiercely pressured me to 'Take all that bread to the slaves of the Most High!' He made me follow him to this place, knocked on the door, and then he vanished. I don't even know where I am."
Hearing all this, the brother reported it to his blessed abbot. The holy Alexander received the bread and served it warm to the brothers, who were already at their tables. With gratitude, they took their share and gave the rest to their brothers, the indigent poor. And [those formerly faithless men] marveled when they saw the unrestrained liberality of him who, in accordance with Scripture, gave no thought to the morrow.
The Life of Alexander the Sleepless III.45