[Excerpted from Orthodox Life, Vol. 33, No. 6, pp. 48-49--which is excerpted 
and slightly re-arranged from The Concern of the Orthodox Church 
for the Salvation of the World by the Rev. G. S. Debolsky 
(translated from the Russian by Maria Naumenko)]

     The custom that Orthodox Christians stand during prayer and church services is not only a representation of spiritual service in the Heavenly Church, but also in the Church of the Old Testament.
     The God-inspired prophets Isaiah, Micah Daniel and St. John the Theologian saw "standing in the heavens next to the throne of God" (Isaiah 6:2; I Kings 22:19; Daniel 7:10; Apocalypse 7:11), Christians similarly should not sit during divine services, but stand.
     In the description of the blessing of Solomon's temple it is said:  "All the congregation of Israel stood" (II Chronicles 6:2).  Another example from tile Bible occurs in tile description of the reign of Josaphat. In order to protect his homeland from the Ammonites and the children of Moab, he "stood in the congregation of Judah in Jerusalem, in the house of the Lord before the new court.  And all Judah stood before the Lord, with their little ones, their wives, and their children" (II Chronicles 20:5, 13).  Ezra and Nehemiah, speaking of the services of the Jews after the Babylonian captivity, say: "And the Levites stood according to their rank and cried with a loud voice unto the Lord their God, and the Levites caused the people to understand the law; and the people stood in their
place" (Nehemiah 9:4,5; 8:7; also Matthew 6:5).
     To stand during prayer was thus it customary rule among the Jews, as
is proved in their writings, in the manner of the Heavenly and the Old Testament Church.

      Orthodox Christians have maintained the custom, since Apostolic times, of standing during divine services.  The correctness of such it practice is evident from New Testament scripture, where we find the words of Christ: "When you all stand praying" (Mark 9:25), and in Apostolic tradition, where it is often proclaimed "Let us stand well."
      Christians, according to the Apostolic teachings, all had to stand during the reading of the Gospel and the "Liturgy of the Faithful."  During other readings and homilies some would stand, others would sit. Tertullian, in the year 190 A.D., mentions the practice of standing during services. He says: "Some, in preparation for prayer, throw off their cloaks, and some think it their duty not to stand,
but to sit, and we are not to imitate these. It is especially improper to pray while sitting at the very time that a multitude of angels stand before the face of the Lord in fear and trepidation; sitting shows that we are somehow praying unwillingly, carelessly, in a lazy manner."