Cantos 13-20

Canto 13 line 142
And I-I made my own house be my gallows.
This line and the longer passage it came from was especially sad to me. It described the stage designed for those who did harm to themselves, or committed suicide. In doing so, these people were hoping to escape pain and despair. Instead, they were thrown into even more of it, probably much more intense and everlasting than what they suffered from before. Once again, this idea of faith seems ironic. Instead of Christianity (& Christians) supporting those who suffer, especially believers who suffer, or relieving those of their suffering, it merely punishes them more if they choose to try to escape it. Is it their fault for leaving a life that by no control of their own was unfair and damaging? What is the purpose of God/the religion not offering hope to those before they commit such crimes?
This line also seems to have a double meaning, one very literal and one more metaphoric. The character speaking literally did kill himself (by hanging) in his house. Once he died, he was sent to this level of Hell where he and everyone else like him were made into trees. When the time comes, they receive their bodies, but these bodies are hung on their branches. Once again, his "house" (his tree form) becomes his "gallows".


Canto 19 lines 1-6
O Simon Magus, and O you wretched crowd
Of those who follow him and prostitute
In your rapacity the things of God
Which should be bridges of righteousness, to get
Silver and gold-it is time the trumpet sounded
For you: the third pouch is where you are put.

In this canto, Dante seems especially angry with the people placed here. Before he decribes the stages as foul-smelling, dirty, and disgusting. He actually pities the people who must suffer there. Here, however, he feels sorry for no one. Before even reaching the inside of this stage, he rants about his hate towards this specific crime. This sin, apparently, is worse than all the others. Perhaps it's especially important to Dante to punish these sinners because he's been personally affected by such people. Because Virgil later approves of Dante's thoughts towards these people, it is implied that the audience should, too. Some torture can invoke sympathy in the audience, but some crime are so harsh that no amount of torture is enough. This passage is the beginning of the canto that shows the difference between what is truly bad and what is perceived to be bad, at least according to Dante.
(According to Wikipedia) Simon Magus is the founder of Simonians and was considered to be a demon by some Christians.
Does Dante condemn those who commit such crimes because of personal experience or because it is also believed in the Christian religion that this is the worst (or one of) of all sins?