The Fast of Catechumens is unique only to the Armenian Church. It begins three weeks before the Great Lent. In ancient times people could eat only bread and salt during the fast of Catechumens. On those days it was not allowed to celebrate Divine Liturgy either.

The meaning of the Fast of Catechumens is the purification of the five human senses from pagan impurity. In the ancient Church there was a custom to fast during five days before baptism. St. Gregory the Illuminator ordered King Tiridates and others to fast for five days before baptism in order to get freed of the evil. That is the reason also for fasting of Catechumens to be called “fast of salvation” from the evil.

According to the tradition, the fasting of Catechumens was initiated by St. Gregory the illuminator in memory of the above-mentioned practice.

There are two explanations regarding the name of this feast.
It is called the fast of Catechumens:
1. As the precursor of the Great Lent, and
2. As the first Armenian fast.

On the fifth day of the fasting of Catechumens, on Friday, the remembrance day of the Prophet Jonah is celebrated, but it is celebrated not as the feast of Prophet Jonah, but as the memory of an example of great repentance and abstinence which Jonah urged. At times, wrongly, the fasting of Catechumens was called the fast of St. Sarkis, because the Armenian Church celebrates the feast of St. Sarkis on Saturday following the fast. In Middle Ages the Byzantine and the Georgian Churches blamed the Armenian Church for the fasting of Catechumens, relating it to St. Sarkis, to whom they ascribed sorcery. According to the testimonies of Armenian medieval writers. Greek and Latin Churches also had the fasting of Catechumens in ancient times.