In the name of mercy, some recent theologians have suggested that there are elements of good in some objectively wrong acts and relationships. For example, friendship is good, and there certainly is an element of friendship in an illicit sexual relationship.
Or for that matter in the collusion of two thieves in a theft. Funny that we don’t apply the argument to theft.
We always stop with sex.
But why? There may be an element of intelligence in a well-planned fraud, an element of the love of kin in genocide, and an element of the love of beauty in the theft of a work of art. Friendship, intelligence, love of kin, and love of beauty are all good in themselves. But this is irrelevant to the question of whether these acts and relationships are wrong.
The question should not be whether there are elements of value in sins, but whether there is anything valuable about sinning.
Consider: No one can love evil for its own sake. The only thing it is possible to will for its own sake is good. Thus, the only way it is even possible to will an evil is that something about it seems good to us.
But something seems good to us in every evil, because evil cannot exist in itself. The only way to get an evil at all is to take something good and distort it.
The upshot is that the fact that evil contains disordered elements of good doesn’t mean it isn’t evil. What this fact shows is why evil can be attractive.
Now back to mercy. If I am hurting myself by what I am doing, if I am hurting others, if I am separating myself from God -- then I want my friends to love me enough to tell me. Lying to me in the name of “elements of good” does not help me. It is not mercy but indifference.
So although it is certainly possible to tell the truth without being merciful, it is impossible to be merciful without telling the truth.