Why should you pray three times a day David, Daniel, and Peter prayed three times a day. They set a model for us to follow.
David said, “Evening and morning and at noon I will pray, and cry aloud, And He shall hear my voice” (Psalm 55:17). Here it specifically says David prayer three times a day
The Prophet Daniel also got down on his knees three times a day and prayed and gave thanks before his God, as he had done previously (Daniel 6:10). This was a habit of the devout.
In Acts 2:15, it says that Peter prayed with the church at the third hour of the day (9 am). In Acts 3:1, “Peter and John went up together to the temple at the hour of prayer, the ninth hour” (3 pm). And in Acts 10:9, Peter went up to housetop to pray at the sixth hour of the day (noon).
This practice was passed down to the early Church. The Didache, the earliest document after the New Testament about Church practice. It says to pray the Lord’s Prayer “three times a day” (8:2-3).
Here we see a set prayer was repeated three times a day. Hence, the foundation for the liturgy of the hours, also know as the Divine Office.