As I read through your thread, I was reminded of an ex-Muslim friend of mine. Let me correct that, ex-Islamist. Happily he is still Muslim.
Anywho, the reason your thread brought Him to mind, is that he was so worried about what his family would do if he told them he had even read the Bible, add to that he had turned from Islam, and embraced Yeshua. He kept it from his family for about 2 years. One day we were talking, and it came up what baptism was. That led to,
Mat 10:33 “But whoever denies Me before men, him I will also deny before My Father who is in heaven.
It was finding an understanding of this passage and it's implications, that led this friend to asking his family to come for his baptism. His mom showed up, along with his sister. His dad on the other hand told him he was dead to him. His family spelt up, and it was not pretty in anyway at all. His mom and sister in time also came to know Yeshua, they now speak out boldly about the evil of Islam, and how they now feel freed from bondage.
I don't pass this on to discourage you, rather to encourage you. You see this friend used his knowledge of Islam to get his dad to see how wrong it was. His dad, who I worked with at that time, also talked about how tolerant Islam was of other religions. How it was in the Koran and so on. His son, has used to point out the wrong in what his dad does, and how he acts toward others.
I do hope this helps you in some way.