I love this, in English theologian J.I. Packer’s, Praying the Lord’s Prayer.
“We should certainly not content ourselves with parroting other people’s prayers, nor would God be content if we did (for what parent could be happy if his child only ever spoke to him in quotations, thus limiting his conversation to the reciting of other people’s sentiments?)”
Yes! Imagine a child, formally and haltingly addressing his parent — with no familiarity, no free spirit, no heart. And yet that is the way we are often taught to pray to God.
Brennan Manning puts it this way: “A little child cannot do a bad coloring; nor can a child of God do bad prayer.”
Just talk to the Father as if he were your dad (because he is), and Jesus as if he were your brother (because he is).