Cross reference
Matthew 26:44
44 And having left them, having gone away again, he prayed a third time, saying the same word;
2 Corinthians 12:8
8 Concerning this thing thrice the Lord did I call upon, that it might depart from me,
Daniel 9:17-19
17 and now, hearken, O our God, unto the prayer of Thy servant, and unto his supplication, and cause Thy face to shine on Thy sanctuary that `is' desolate, for the Lord's sake.
18 `Incline, O my God, Thine ear, and hear, open Thine eyes and see our desolations, and the city on which Thy name is called; for not for our righteous acts are we causing our supplications to fall before Thee, but for Thy mercies that `are' many.
19 O lord, hear, O Lord, forgive; O Lord, attend and do; do not delay, for Thine own sake, O my God, for Thy name is called on Thy city, and on Thy people.'
Matthew 6:7
7 `And -- praying -- ye may not use vain repetitions like the nations, for they think that in their much speaking they shall be heard,
Luke 18:1
1 And he spake also a simile to them, that it behoveth `us' always to pray, and not to faint,