Chapter XXI. Justa's Adopted Sons, Associates with Simon
“These men having fallen in with Zacchæus, who sojourned here, and having received the word of truth from him, and having repented of their former innovations, and immediately denouncing Simon as being privy with him in all things, as soon as I came to sojourn here, they came to me with their foster-mother, being presented to me by him, Zacchæus, and ever since they continue with me, enjoying instructions in the truth.” When Peter had said this, he sent for them, and charged them that they should accurately relate to me all things concerning Simon. And they, having called God to witness that in nothing they would falsify, proceeded with the relation.
Source: Clementine Homilies (New Advent)