Following from my previous post, and from what Cardinal Kasper said.
Since it is the month of May, traditionally dedicated to Our Lady, I recommend Blessed John Henry Newman's University Sermon XV on the development of doctrine where he explains firstly the Blessed Virgin as the model theologian, pondering those things of belief in her heart, and secondly, the way the truth is passed down. Doctrine is formulated as things counter our impression of the truth in our heart, when something is presented that doesn't seem quite right with the Church's teaching. We then come to a more perfect profession of faith. The truth can be held, even if one can't articulate it, as a poor peasant might, or if it can be attempted, perhaps in the case of someone very much like Newman.
Yes, I have said myself that mercy is excessive justice, going beyond what is the other's due. I would recommend reading the Catechism's teaching on the commandments in order to more fully understand justice, both that given to God in the virtue of religion and justice towards others on our individual level and in society. And we all must have mercy, we must love for that is what we are called to do at all times in all places. Christ gives the new law of charity, fulfilling the old law in the process and redirecting us to our original vocation. To not love is to put us in peril of damnation, but no one is forcing us. Otherwise it would not be love. So on the other hand, the Good Samaritan was certainly obliged to avoid robbing the man and avoid beating him but it was in his own will moved by grace that he loved him. Also, irresistible movements do not equal coercion. It's subtle, but it's true. As to the original question, it involves not one, not two, but three parties. Perhaps that was understood, but we see in the Lord's Prayer: "Forgive us our trespasses, as we forgive those who trespass against us." Extend that to our own need to seek forgiveness from others whom we have trespassed against. I also really need to read some works by Emmanuel Levinas, the philosopher; I was intrigued by the cardinal's remarks on personhood.
The cardinal describes as is so common Confession as the sacrament of mercy. But I would like to develop the idea of Holy Communion as the sacrament of mercy above all. (Yes, I know, I probably have a dozen items I need to blog about, like the family as the domestic monastery...).
To be continued...