Matthew 18:12

Irenaeus Against Heresies Book I

Thus she, passing from body to body, and suffering insults in every one of them, at last became a common prostitute; and she it was that was meant by the lost sheep.[284]

Constitutions of the Holy Apostles Book II

But do thou, like a compassionate shepherd, and a diligent feeder of the flock, search out, and keep an account of thy flock. Seek that which is wanting;[110]

Origen Commentary on Matthew Book XIII

[As for the exposition of the matters relating to "the hundred sheep," you may consult the homilies on Luke.[190]