Amy Carmichael said this quote
“ We have one crystal clear reason apart from the blessed happiness of this way of life. It is this: prayer is the core of our day. Take prayer out, and the day would collapse, would be pithless, a straw blown in the wind. But how can you pray--really pray, I mean--with one against who you have a grudge or whom you have been discussing critically with another? Try it. You will find it cannot be done. ”