What are some of the things the Bible says about the importance of prayer?

Matthew 26:41 (NIV)

“Watch and pray so that you will not fall into temptation. The spirit is willing, but the flesh is weak.

1 Thessalonians 5:16-18 (NASB)

“Rejoice always; pray without ceasing; in everything give thanks; for this is God’s will for you in Christ Jesus.”

Matthew 26:41 (NASB)

“Keep watching and praying that you may not enter into temptation; the spirit is willing, but the flesh is weak.” 

Philippians 4:6 (NASB)

 “Be anxious for nothing, but in everything by prayer and supplication, with thanksgiving, let your requests be made known to God.”

1 Timothy 2:1-4 (NIV)

“I urge, then, first of all, that requests  prayers, intercession and thanksgiving be made for everyone – for kings and all those in authority, that we may live peaceful and quiet lives in all godliness and holiness. This is good, and pleases God our Savior who wants all men to be saved and to come to a knowledge of the truth.”

Romans 8:26-27 (NIV)

“In the same way, the Spirit helps us in our weakness. We do not know what to pray for, but the Spirit himself intercedes for us with groans that words cannot express. And he who searches our hearts knows the mind of the Spirit, because the Spirit intercedes for the saints in accordance with God’s will.”

James 5:16 (NIV)

“Therefore, confess your sins to each another and pray for each another so that you may be healed. The prayer of a righteous person is powerful and effective.”