Luke 18:1

And he spake a parable to them to this end, that they ought always to pray, and not to faint;

Philippians 4:6

Be careful for nothing, but in every thing by prayer and supplication with thanksgiving let your requests be made known to God:

Colossians 4:2

Continue in prayer, and watch therein with thanksgiving:

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
And he spake a parable to them to this end, that they ought always to pray, and not to faint;
Philippians 4:6
Be careful for nothing, but in every thing by prayer and supplication with thanksgiving let your requests be made known to God:
Colossians 4:2
Continue in prayer, and watch therein with thanksgiving: