Ephesians 6:18

18. praying always with all prayer and supplication in the Spirit, being watchful to this end with all perseverance and supplication for all the saints-

I Thessalonians 5:17

17. pray without ceasing,

Hebrews 4:14-16

14. Seeing then that we have a great High Priest who has passed through the heavens, Jesus the Son of God, let us hold fast our confession. 
15. For we do not have a High Priest who cannot sympathize with our weaknesses, but was in all points tempted as we are, yet without sin. 
16. Let us therefore come boldly to the throne of grace, that we may obtain mercy and find grace to help in time of need.

James 5:16

16. Confess your trespasses to one another, and pray for one another, that you may be healed. The effective, fervent prayer of a righteous man avails much.