1 Thessalonians 5:16-18 (NIV)
"(16) Rejoice always, (17) pray continually, (18) give thanks in all circumstances; for this is God’s will for you in Christ Jesus."

Prayer is a means of communication with God in terms of thanksgiving, request and many more.
According to dictionary::
Prayer is a solemn request for help or expression of thanks addressed to God or another deity.

But as a believer we need to pray at all time in other to remind God of what our heart desire.
Prayer is also used to fight the unseen battle e.g spiritual battle and its also used to bring down the presence of God.

HOW DO WE PRAY WITHOUT CEASING

• Begins with praise and worship because God walk through praise and worship. During praise battle are been won, captive are been delivered.

• Hold God by his word: This is because God honour his word than his name.

So pray without ceasing