state reasons why christians in the early church prayed
https://www.google.com/search?q=why+prayer+is+central+to+christianity&oq=why&aqs=chrome.0.69i59j69i57j69i59l2j69i60l3j69i65.2664j0j7&sourceid=chrome&ie=UTF-8
Mostly because Jesus said to, but you can find specific biblical references in these search results.