Honesty is the key to all morality. If a person isn't honest, then he is essentially reserving the right to lie about what he did and thus avoid any associated moral duty that he may have breached. A person who chooses his "facts" based on how they make him feel is fundamentally dishonest. He is lying to anyone and everyone, including himself, whenever he feels like it.
It has been my direct, personal experience that the religious reserve the right to lie whenever they feel like it. Of course, they rationalize it in their minds, and, if need be, will ask their invisible friend to forgive them so that any nagging pangs of conscience will stop bothering them. (So much for religious morality.)
There can be no justice in this world if the truth is kept hidden. And, as one so often hears, there can be no peace without justice. Putting aside the concern for peace, I can't begin to understand how anyone could have so little empathy for others that he would tolerate a world of injustice.
What this all boils down to is this:
"If you aren't honest, you are an enemy of the truth. If you are an enemy of the truth, then you are an enemy of justice. If you are an enemy of justice, then you are an enemy of peace and virtually anything else that can be considered good in this world."