Luke 18:1

He also taught them by a parable how they ought always to pray and never to lose heart.

Philippians 4:6

Do not worry about anything; but in everything by prayer and supplication, with thanksgiving, let your requests be made known to God;

Colossians 4:2

Be unwearied in prayer, and keep awake in it when giving thanks.

Treasury of Scripture Knowledge

Summary

Because he hath inclined his ear unto me, therefore will I call upon him as long as I live.

Bible References

Therefore

Luke 18:1
He also taught them by a parable how they ought always to pray and never to lose heart.
Philippians 4:6
Do not worry about anything; but in everything by prayer and supplication, with thanksgiving, let your requests be made known to God;
Colossians 4:2
Be unwearied in prayer, and keep awake in it when giving thanks.