The Shape of Baptism: The Rite of Christian Initiation
Pueblo Publishing Co.
“The Apostolic Tradition [early Church document] says only that those who come forward for the first time to “hear the word” should be presented to the teachers of the community privately so that their motives can be examined and vouched for the “those who bring them.” Admission to “hear the word” is not a mere formality: whole classes of people- such as pimps, teachers of pagan philosophy, pagan priests, makers of idols or amulets, and men with concubines –are not accepted into this class of learners, or catechumens, unless they first forsake their modes of life. The crux of admission procedure has nothing to say about the intentions of the applicant: it is in his manner of living that is to be ascertained and, apparently, nothing more. From this point on, the applicant, if accepted into the Catechumenate, will be expected to be living in a manner befitting a Christian…”
The Foundation of Liturgy: An Introduction of Its History and Practice
The Liturgical Press
The Office of Sponsor:
“The duty of sponsors was to be guarantors to the community of the serious intentions and authentic conversion of the catechumens.”
Council of Nicea: Canon 12 reads as follows: "Those who by fear and tears and patience and good works prove that their conversion is real and not simulated, when they have completed the prescribed time among the hearers, may fittingly participate in the prayers after which it is at the discretion of the bishop to treat them with an even greater kindness."
The Council of Elvira: "If it is determined that youths who have fornicated after having been baptized may, when they have done legitimate penance and when they have been married, be admitted to communion." (around 300 A.D.)