From the letters of Fr. Clement Sederholm (1830-1878) to his father.
I can briefly explain to you concerning prolonged prayers in our [Orthodox] Church. Every one of us prays not for himself only and not in their own way. We gather together for common church prayer in order to fulfill the unity and mutual love which is commanded by the Holy Spirit as well as what is prescribed by the apostle: forsake not the assembly as do some (Heb. 10:25). No matter how elevated the apostles stood they did not remove themselves from the assembly of believers (Acts 3:1). And that a few prayers of the Church are stronger than the prayers of one man can be seen from the fact that the Apostle Peter was freed from prison by the prayers of the Church (Acts 12:5-19). Our church prayers are made up of psalms, church songs, and various prayers. Every person praying follows the church prayers as they can: if his thoughts scatter he can quickly gather his senses and again follow after the course of the service and pray. But when someone prays alone and composes prayers himself then if his thoughts scatter it is harder for him for begin again to pray; and where does he start? If you, at your age and after long years of studying lofty subjects, feel how hard it is to keep your thoughts together, what can be said about a beginner? Concerning those who already reached the a high level of spiritual life, they add their short prayers to the common church prayer.
I heartily wish that my explanation turns out to be satisfactory to you.
Taken from Blog Incendiary
More on Prayer
6 minutes ago