If we sum up all of Christianity this way, it would be obviously ridiculous. What people do not understand is that from God’s own POV every aspect of reality is just something that he made up.
When we ask the question is Jesus really the son of God? The answer is quite unexpected. If God is the creator of all things, then even the concept of fatherhood and sonship is just something that he made up.
Since there cannot possibly be any ultimate reason for existence (because existence itself would necessarily precede any reason for it) any reason for existence must be artificially contrived after-the-fact.
By all the power of God that I am I hereby update the above story: The purpose of existence is joy. Righteousness is defined as what-so-ever maximizes peace and joy. It is just as simple as that.