¿Why is prayer essential in the Christian ?

The Bible says that when the Lord appeared in the upper room on the day of Pentecost, the first thing he did was to instruct his disciples about prayer. He told them: "persevere in prayer and petition." They had established priorities and prayer ranked first. From the first day of action in the upper room, the note that would characterize the future of the Christian church's ministry was given. Even a simple business session would always begin with prayer.

If someone really gives his life to the Lord Jesus, he will hardly turn away from God in the midst of trial, pain or tragedy. And seek to persevere in prayer at all times.

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And it is evident that prayer is your communication with God. So everything that is going to make any plan that has to execute any problem that has to solve ... everything must go to God in prayer to be within the plan of God.
The history of the church in the book of Acts exalts the ministry of prayer and exemplifies that without prayer there will be no victory.

Those examples observed in the early church remind us that we should never neglect vigilance in prayer even after experiencing the most remarkable victories in the Lord.

The example of the Lord himself had left a deep impression on the twelve. One day, on arriving at the secret place where the teacher spent long hours in communion with the father, the disciples were so impressed that they begged him saying: "Lord, teach us to pray".
How important is prayer, I believe it is one of the most powerful tools of the Christian, prayer gives you faith hope because through it you expect an answer.