Ante-Nicene Fathers, Vol VIII:
Pseudo-Clementine Literature.: Chapter XXXIV

Chapter XXXIV.—Baptism Must Be Preceded by Fasting.

When Niceta had spoken thus, our mother fell down at Peter’s feet, entreating and beseeching him that both herself and her hostess might be baptized without delay; “that,” said she, “I may not even for a single day suffer the loss of the company and society of my sons.”  In like manner, we her sons also entreated Peter.  But he said:  “What!  Do you think that I alone am unpitiful, and that I do not wish you to enjoy your mother’s society at meals?  But she must fast at least one day first, and so be baptized; and this because I have heard from her a certain declaration, by which her faith has been made manifest to me, and which has given evidence of her belief; otherwise she must have been instructed and taught many days before she could have been baptized.”