The answer
According to the Apostolic Constitutions, “The church must be rectangular in form and pointing to the East.”1193 This tradition was mentioned in the writings of many early Fathers including St. Clement of Alexandria,1194 Origen,1195 and Tertullian,1196 etc. It was almost invariably observed in all churches. Furthermore, the Liturgy of Baptism was also observed this tradition in the early Church. First, the catechumen faced the west and renounced the devil and all his works; then he would be asked to face the East to profess his faith in the Holy Trinity.1197 We also read of St. Arsenius that he was accustomed to commence his prayer at sunset on Saturday and finish it when the sun shone opposite him on the following morning. Also, in The Acts of the Martyrs, we read that the martyrs used to exert every effort to face the east at the time of their martyrdom or departure from this world.
Fr. Tadros Yacoub Malaty
Notes
1193 Constitutions of the Holy Apostles 2, 57 (ANF 7:421).
1194 St. Clement of Alexandria, The Stromata, or Miscellanies 7.7 (ANF 2:535).
1195 Origen, Homilies on Numbers, trans., Thomas P. Scheck (Downers Grove, Illinois: IVP Academic, 2009) 5.1.4: p. 17.
1196 Tertullian, Apology 16 (ANF 3:31); Ad Nationes (To the Nations) 1.13 (ANF 3:123).
1197 Cf. St. Cyril of Jerusalem, Catechetical Lectures (NPNF II/7).