I think Father Wicks actually fathered Monsignor Wicks. I think he sexually abused Grace and got her pregnant and kept her "under his roof" to keep it a secret.
1.) The diamond being named Eve's Apple when Eve is treated as the "original temptress" and most Christians interpret the apple thing as being exclusively the fault of Eve and her tits. Sin is seen as emanating from women and men's actions are blamed on that sin
2.) Catholicism and Christianity at large teach men that they are not truly capable of controlling themselves and if they harm a woman or even their own daughters, it's because said woman tempted them, and gives them permission to be angry at their victims for "seducing" them
3.) In chapter 19 of Genesis, Lot's daughters get him wasted in order to seduce him; this is, of course, one of the cultural narratives that is used to justify father-daughter sexual abuse. "It was HER idea SHE seduced ME if anything I'M the victim here!" This is relevant because Father Wicks preaching style would likely lean very heavily on the story of Sodom and Gomorrah
3.5) Earlier in the saga of Sodom and Gomorrah, Lot offers his virgin daughters to a crowd of rapists as a distraction; the crowd is seeking to gang rape two (male) angels and Lot gives them his young daughters in exchange. The honor of women is disposable and can be exchanged for preserving the virtue and dignity of men.
4.) Mary is the bride of god, but Trinitarian doctrine, plus the idea of God as Patriarch, means that she is the "bride" of her father AND her son. There is no Marion iconography in the church. I cannot stress enough that no catholic parish on earth would hold mass without (with great emphasis) SHE.
5.) It is pretty standard practice for perpetrators of sexual violence to do deliberate damage to their victim's reputation and make it difficult for them to get anyone to help or even believe them, and literally everyone called Grace a whore AT HER FATHER'S PROMPTING
6.) Grace's terror and outrage are so intense in her death scene. She's so desperate to get away from her father's house and while I fully believe that IRL emotional abuse can make you that insane, most movies don't give purely emotional abuse that sort of gravity: to me, she was framed like a person who'd been violated, or like a slave fleeing captivity.
7.) Monsignor Wicks' behavior clearly indicates that he thinks of sexual impropriety as normal and not a big deal, meaning his childhood home likely lacked appropriate boundaries
8.) Martha tells us that Father Wicks was a widower and Grace was living alone with him. 'Daughter as a sexual replacement for dead wife' is a depressingly common trope in American fiction.
9.) "Harlot Whore" is redundant...until you remember that Harlot did not always refer to a prostitute. It sometimes refers to a male drifter or to a lecherous old man.
