Canon 14
On penance for those who fell from among the catechumens, but were not baptized (3 years).
Concerning the catechumens and the fallen, the holy great Council decided that they should remain listening only for three years, and after that they should pray with the catechumens.
Greek original
Περὶ τῶν κατηχουμένων, καὶ παραπεσόντων, ἔδοξε τῇ ἁγίᾳ καὶ μεγάλῃ συνόδῳ, ὥστε, τριῶν ἐτῶν αὐτοὺς ἀκροωμένους μόνον, μετὰ ταῦτα εὔχεσθαι μετὰ τῶν κατηχουμένων.
Parallel canons
IВс.2111213Трул.96Неокес.5Лаод.19Вас.20Тимоф.4Кир.5