There are seven sacraments in the Orthodox Church. The first sacrament for a Christian after entering the Church is holy baptism. In it, a person is adopted by God.
In the modern practice of the ROC, the sacrament of baptism is performed together with another priesthood - chrismation. Therefore, we should talk about the time of the sacrament of baptism in accordance with this practice of combining the two sacraments.
Most often, baptism in Orthodox churches is performed non-individually. That is, several people at once are honored with the sacrament of joining the Church as a society of people who believe in the Holy Trinity, united by a single hierarchy. Depending on the total number of those who are baptized, we can also talk about how long holy baptism takes.
If the sacrament of baptism is performed on one person, then (together with chrismation) it takes about forty minutes. This time is quite enough for the priest to read the necessary prayers, as well as perform the necessary sacred rites. If there are more people who are baptized, for example, ten to fifteen people, then the baptism can take about an hour. This difference is due to the fact that during the sacrament of baptism, the priest performs certain sacred rites over each baptized person.
In addition, it should be borne in mind that some clergymen, immediately before or after baptism, pronounce a parting word to people, which may take some time. In some churches, before baptism, small public discourses are read, which take an hour or an hour and a half. Thus, on average, the sacrament of baptism itself can take 40-60 minutes, and in the case of public discourses and preaching, a person may need up to two and a half hours of being in the temple to receive the sacrament.