Paul in 1 Thessalonians 5:17-18 declares that God’s will for us is that we
[p]ray without ceasing. In every thing give thanks.
To pray unceasingly does not mean spending twenty-four hours daily in prayer. >b>Rather, it means being open continually to God, sharing our thoughts and hopes with Him in mental prayer, and so on. It means, as we face a problem, praying, in a sentence, “Lord, help me 
with this problem”; or, “Give me patience as I talk with this trying person”; or, “Thank you for seeing me through that mess,” and similar prayers.
O. Hallesby years ago wrote, “We cannot breathe in the early morning in such a way that it will be sufficient until noon. Likewise, we cannot pray in the morning so as to suffice until noon.”
Continual sentence prayers are simply Christian breathing. They keep us alive and strong.
Together with such praying, Paul says, must go thankfulness: “In every thing give thanks.” We resent it when people we help are ungrateful and see no need to thank us. We had better beware of being similarly ungrateful to God. We complain about our troubles to Him. Do we thank Him for our blessings, for loved ones and friends?
The Lord has no use for long-winded prayers. He does expect and require gratitude, and a heart open to Him.
R. J. Rushdoony, Taken from A Word in Season, Vol. 5, p. 114f.