Why doesn’t God intervene to help people in prolonged and terrible suffering?

[Young86]

Correct me if I'm wrong but doesn't "Karma" refer to past incarnations. If so, that would surely be anti-Christian because as I understand it, we only have one life and then comes the Judgement.

Yes, it refers. No, that is what you believe..in other religions people mention karma, past lives. God created all religions because the spiritual reality is very complex. Everybody should follow their own religion but all religions are the same in fact. You had past lives. You will have future lives unless you change and become a pure saint and go to heaven. If you don't you will end up in hell or as I could understand in the state of spirit and you will watch others who knows how much years.. Murderers, rapists, heavy sinners will reincarnate in 1000 or more, I don't know.