If we take prayerfulness out of Christianity then our Christianity is not complete. When Jesus carried out his ministry on Earth he didn't put aside the aspect of prayers. One of the foundational blocks that sustain Jesus in fulfilling his mission on Earth was prayers.
Prayer helps us in a lot of ways in our Christian journey. It should be a lifestyle and not something we do occasionally or what you feel like. If we only pray when we feel like then we are not doing the right thing. The book 1 Thessalonians chapter 5 gave us an instruction to always pray without seizing. When we stop praying we put ourselves at risk.
Prayer is a very powerful tool that we are Christians use. The world we live in today is a battlefield right from the times of old. During the Old testament they were various records of kingdoms going to war with each other. But in our present time we don't really make use of swords in the to go to battle.
The tool that God gave us in this our present time to be able to overcome the enemy is prayers and that is why we should not joke with it.