Tradition
St. Benedict of Nursia
The Rule of St. Benedict
Chapter XXIX. Whether Brethren Who Leave the Monastery Ought to Be Received Again
CHAPTER XXIX
Whether Brethren Who Leave the Monastery Ought to Be Received Again
If a brother, who through his own fault leaveth the monastery or is expelled, desireth to return, let him first promise full amendment of the fault for which he left; and thus let him be received in the last place, that by this means his humility may be tried. If he should leave again, let him be received even a third time, knowing that after this every means of return will be denied him.
Source: The Rule of St. Benedict (CCEL)