Where is there a warrant for the convent system outside your Catholic traditions?

The Catholic Answers

There is more than sufficient warrant for convent life in Sacred Scripture. But even were the only warrant to be found in Catholic traditions, that surely would be quite a natural place to seek a warrant for a Catholic custom. Where else would you want me to find a warrant for it? In Totemism?

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty