Nicene and Post-Nicene Fathers, Ser. II, Vol. XIV:
The Canons of the Council in Trullo; Often Called The Quinisext Council.: Canon XLVIII

p. 388 Canon XLVIII.

The wife of him who is advanced to the Episcopal dignity, shall be separated from her husband by their mutual consent, and after his ordination and consecration to the episcopate she shall enter a monastery situated at a distance from the abode of the bishop, and there let her enjoy the bishop’s provision.  And if she is deemed worthy she may be advanced to the dignity of a deaconess.

Notes.

Ancient Epitome of Canon XLVIII.

She who is separated from one about to be consecrated bishop, shall enter a monastery after his ordination, situated at a distance from the See city, and she shall be provided for by the bishop.