Throughout the centuries, various religions have come up with various prescriptions that were designed specifically to be a response to God's will for mankind, and for the spiritual healing of mankind as it's reward. These prescriptions tend to be direct reflections of the image of God the various religions profess and promote, and the promised results tend to exemplify an idealization of mankind's proper condition in "God's eyes".
It's important to understand that these kinds of prescriptions are the direct result of a specific God-concept, being acted upon as one believes God wishes, in hopes of achieving the results that God has promised, and which mankind rightfully deserves.
A classic example of such a prescription might look something like this:
1. To pray for humility.
2. To reflect upon one's "sins".
3. To confess these sins to a priest or minister.
4. To make some act of contrition or restitution for the damage these sins have done to others.
5. Repeat previous steps for all future "sins".
This and similar prescriptions have been practiced over the centuries by countless humans beings from various religious traditions and ideologies, and most found that through this prescription they achieved pretty much exactly what was promised. It's a simple but effective way of learning to alter one's own behavior in favor of an ideal based on the concept of "God".
A concept of God, when acted upon according to that idea, produces the results that the idea itself promises. I believe this is evidence in the same way any other idea is ratified by testing it through action.
A similar idea might be something like: Carol claims she loves Bill, and wants to marry Bill and live with Bill as his wife. But BIll is skeptical, so he proposes that they live together unmarried for a time, to see how it goes. But as they live together, Bill discovers that Carol does not behave as a woman who loves her husband, but as a woman who wants to possess him, and control him, and punish him when he does not oblige her needs. She says she loves him, and wants to be his wife, but she doesn't act as if she loves him, nor does she treat him like a husband. Bill was presented with an idea. And he wanted to find out if that idea had correspondence in reality (the measure of truth). So he lived as if the idea was "real" for whatever length of time it took for him to satisfy himself that it either was or was not actually true. In this case, Bill discovered that the idea was false. It did not have correspondence in actuality.
The religious prescription I posted, above, has been tried and tested by millions of human beings, throughout centuries, and found to work for them as claimed.