Luke 11:8-10
I tell you, though he will not get up and give you anything because you are a friend of his, he will at least rise and give you whatever you want, because you persist.
Luke 18:1
He also told them a parable about the need of always praying and never losing heart.
Ephesians 6:18
praying at all times in the Spirit with all manner of prayer and entreaty ??be alive to that, attend to it unceasingly, interceding on behalf of all the saints
Colossians 4:2
Attend to your prayers, maintain your zest for prayer by thanksgiving;
1 Thessalonians 5:17
never give up prayer,
James 5:16
So confess your sins to one another and pray for one another, that you may be healed; the prayers of the righteous have a powerful effect.