In a talk entitled "Legalism, Moral Truth and Pastoral Practice" given at a 1990 symposium in Philadelphia, Dr. Germain Grisez explained to those present that, "Theologians and pastors who dissent from received Catholic teaching think they are rejecting legalism because they set aside what they think are mere rules in favor of what they feel are more reasonable standards. Their views are thoroughly imbued with legalism, however. For dissenters think of valid moral norms as rules formulated to protect relevant values. Some even make their legalism explicit by denying that there is any necessary connection between moral goodness (which they restrict to the transcendental level of a love with no specific content) and right action (which they isolate at the categorical level of inner-worldly behavior). But whether their legalism is explicit or not, all the dissenters hold that specific moral norms admit exceptions whenever, all things considered, making an exception seems the best - or least bad - thing to do. Most dissenters also think that specific moral norms that were valid in times past can be inappropriate today, and so they regard the Church’s contested moral teachings as outdated rules that the Church should change."
It would seem that Francis has succumbed to such a legalism, for he has once again implied that the Church's moral norms are merely "a set of rules and regulations." See here.
Dr. Grisez reminded his listeners at the Philadelphia symposium, "During the twentieth century, pastoral treatment of repetitious sins through weakness - especially masturbation, homosexual behavior, premarital sex play and contraception within marriage - grew increasingly mild. Pastors correctly recognized that weakness and immaturity can lessen such sins’ malice. Thinking legalistically, they did not pay enough attention to the sins’ inherent badness and harmfulness, and they developed the idea that people can freely choose to do something that they regard as a grave matter without committing a mortal sin. This idea presupposes that in making choices people are not responsible precisely for choosing what they choose. That presupposition makes sense within a legalistic framework, because lawgivers can take into account mitigating factors and limit legal culpability. But it makes no sense for morality correctly understood, because moral responsibility in itself is not something attached to moral acts but simply is moral agents’ self-determination in making free choices. Repetitious sinners through weakness also were handicapped by their own legalism. Not seeing the inherent badness of their sins, they felt that they were only violating inscrutable rules. When temptation grew strong, they had little motive to resist, especially because they could easily go to confession and have the violation fixed. Beginning on Saturday they were holy; by Friday they were again sinners. This cyclic sanctity robbed many people’s lives of Christian dynamism and contributed to the dry rot in the Church that became manifest in the 1960s, when the waves of sexual permissiveness battered her."
Dr. Grisez goes on to explain that, "Pastors free of legalism will teach the faithful how sin makes moral requirements seem to be alien impositions, help them see through this illusion, and encourage them to look forward to and experience the freedom of God’s children, who rejoice in the fruit of the Spirit and no longer experience the constraint of law..They will explain that while one sometimes must choose contrary to positive laws and cannot always meet their requirements, one always can choose in truth and abide in love. They will acknowledge the paradox of freedom - that we seem unable to resist freely choosing to sin - the paradox that Saint Paul neatly formulates: ‘I do not understand my own actions. For I do not do what I want, but I do the very thing I hate’ (Romans 7:15). But they also will proclaim the liberating power of grace, and help the faithful learn by experience that when one comes to understand the inherent evil of sin and intrinsic beauty of goodness, enjoys the support of a community of faith whose members bear one another’s burdens, begs God for His help, and confidently expects it, then the Spirit of Him who raised Jesus from the dead raises him from his sins, and he discovers that with the Spirit’s grace one can consistently resist sin and choose life."
The faithful deserve an authentic Shepherd who helps them live Jesus' Law of Love - If you love Me, keep My Commandments (John 14:15), not a legalist who views unchangeable moral norms as "mere rules."