Concerning catechumens who have lapsed, the holy and great Synod has decreed that, after they have passed three years only as hearers, they shall pray with the catechumens.
If any of the catechumens shall have fallen for three years he shall be a hearer only, and then let him pray with the catechumens.
The people formerly were divided into three classes in the church, for there were catechumens, faithful, and penitents; but it is clear from the present canon there were two kinds of catechumens: one consisting of those who heard the Word of God, and wished to become Christians, but had not yet desired baptism; these were called “hearers.” Others who were of long standing, and were properly trained in the faith, and desired baptism—these were called “competentes.”
p. 32 There is difference of opinion among the learned as to whether there was not a third or even a fourth class of catechumens. Bingham and Card. Bona, while not agreeing in particular points, agree in affirming that there were more than two classes. Binghams first class are those not allowed to enter the church, the ἐξωθούμενοι , but the affirmation of the existence of such a class rests only on a very forced explanation of canon five of Neocæsarea. The second class, the hearers, audientes, rests on better evidence. These were not allowed to stay while the Holy Mysteries were celebrated, and their expulsion gave rise to the distinction between the “Mass of the Catechumens” (Missa Catechumenorum) and the “Mass of the Faithful” (Missa Fidelium). Nor were they suffered to hear the Creed or the Our Father. Writers who multiply the classes insert here some who knelt and prayed, called Prostrati or Genuflectentes (the same name as was given to one of the grades of penitence).
(Edw. H. Plumptre in Dict. Christ. Antiq. s.v. Catechumens.)
After these stages had been traversed each with its appropriate instruction, the catechumens gave in their names as applicants for baptism, and were known accordingly as Competentes (συναιτοῦντες ). This was done commonly at the beginning of the Quadragesimal fast, and the instruction, carried on through the whole of that period, was fuller and more public in its nature (Cyril Hieros. Catech. i. 5; Hieron. Ep. 61, ad Pammach. c. 4). To catechumens in this stage the great articles of the Creed, the nature of the Sacraments, the penitential discipline of the Church, were explained, as in the Catechetical Lectures of Cyril of Jerusalem, with dogmatic precision. Special examinations and inquiries into character were made at intervals during the forty days. It was a time for fasting and watching and prayer (Const. Apost. viii. 5; 4 C. Carth. c. 85; Tertull. De Bapt. c. 20; Cyril. l. c.) and, in the case of those who were married, of the strictest continence (August. De fide et oper. v. 8). Those who passed through the ordeal were known as the perfectiores (τελειώτεροι ), the electi, or in the nomenclature of the Eastern Church as βαπτιζόμενοι or φωτιζόμενοι , the present participle being used of course with a future or gerundial sense. Their names were inscribed as such in the album or register of the church. They were taught, but not till a few days before their baptism, the Creed and the Lords Prayer which they were to use after it. The periods for this registration varied, naturally enough, in different churches. At Jerusalem it was done on the second (Cyril. Catech. iii.), in Africa on the fourth Sunday in Lent (August. Serm. 213), and this was the time at which the candidate, if so disposed, might lay aside his old heathen or Jewish name and take one more specifically Christian (Socrat. H. E. vii. 21).…It is only necessary to notice here that the Sacramentum Catechumenorum of which Augustine speaks (De Peccat. Merit. ii. 26) as given apparently at or about the time of their first admission by imposition of hands, was probably the εὐλογίαι or panis benedictus, and not, as Bingham and Augusti maintain, the salt which was given with milk and honey after baptism.