I had a pretty religious (Christian) friend from the UK (of the same age as me - late 20's) and we often used to talk about Quran and Gospel (she had knowledge of both and so did I) and it leads to often very interesting discussions and new questions.
She told me about her boyfriend who was an Arab Muslim and actually he was not as religious but pretty stern at Beliefs. Both wanted to marry each other but their parents were against this marriage; one day I asked her couple of questions:
- Suppose you got married to him, will your kids believe in One Allah or Trinity?
She replied that "they will believe in Trinity - though he doesn't agree with me here and says its polytheism". I thought that this marriage (maybe I am wrong) is not going to work but to confirm, I asked a couple more questions and they confirmed that there is a deadlock between two.
I wanted to bring her out of this situation, so being not only a friend but as an inter-faith discussion as well, I suggested her to revise her decision to marry a Muslim as it's not going to work but she did mind that "I am interfering in her personal life" - while I had no intention whatsoever to interfere in her personal life but just to give her advice as per Beliefs conflict.
I wanted to convey but that you should discuss religious differences and how to raise your children should be before getting married. Sadly, I lost a friend in the process - she never talked with me again.
What could have been the better way of recommending the same thing if you were in my place?
P.S: Kindly note that she (or me) never minded any of the questions during our discussions and our questions used to be pretty serious ones.
Information added from comments:
- The conversation was done over text. I didn't use any harsh words (and I don't use emojis - especially in serious discussions) and she was far away from being touchy - I have even asked her questions like "Why Christ (Peace on him) didn't have a son?" and she replied to it as well as "Very interesting question! Give me time to think an answer."
- I had asked her about personal details before (her about her family/work and even about her bf), but never personal decisions. She never hesitated in answering of those questions.