Do not pray as the hypocrites, but as the Lord commanded (THE DIDACHE).
The Christian prays in thought during every hour, being by love allied to God (CLEMENT OF ALEXANDRIA).
To explain the meaning of praying as the hypocrites,
both TERTULLIAN and CYPRIAN pointed to the story of the Pharisee and the publican (Luke 18:1-10).
Let all the faithful pray to God early in the morning when they awake from sleep (HIPPOLYTUS, CYPRIAN).
God is the hearer of the heart, not of the voice (CLEMENT OF ALEXANDRIA, TERTULLIAN, CYPRIAN).
Those who pray for the sake of human glory have received their reward (ORIGEN).
The Lord has bidden us to pray in secret, which is best suited to faith, that we may know that God is everywhere present (TERTULLIAN, CYPRIAN).
We ought not to make our prayers like heathen babbling or wordiness (ORIGEN).
In some quotations below, the early Christians make mention of the third, sixth, and ninth hours (TERTULLIAN, CYPRIAN),
which were regarded sacred to the three persons of the Trinity (TERTULLIAN, CYPRIAN).
Also they were considered as the hours of the beginning, middle, and close of our Lord’s passion
(cf. Matthew 27:45-46; Mark 15:25, 33-34: Luke 23:44; John 19:14).
Praying three times a day was also in accordance with Jewish tradition (cf. Daniel 6:10; Psalms 55:17; Acts 3:1; 10:9).
Clearly these specified times of prayer are not commanded in Scripture, but these traditions are observed very early in Christian history.
TERTULLIAN acknowledged that nothing at all had been prescribed concerning the times of prayer, except “to pray at every time and every place”
(cf. Ephesians 6:18; 1 Thessalonians 5:17; 1 Timothy 2:8).