What religion is a person?

What religion is a person.... who lets say learned about Islam and the Quran as a teenager. they loved reading the Quran and enjoyed the topic of relgious studies. They believed in their heart that Muhammed was the messanger and believed Jesus was a prophet but they never officially joined Islam. Never confessed it formally at a place of worship because the culture adjustment would be to hard to handle. Instead because their family is of European Christain roots and their families goes to Chruch. They instead continued going to Christian chruches... out of culture not necessarily their true faith. They wanted to fit in with their family... but in privacy they would always read the Quran. They didn't want to be abandoned by family so just stayed Christian and went to Christian churches...because they wanted to conform and not get retaliation from family.... They figured maybe one day when family members pass away and family members grow apart he would offically join Islam in the presense of 3 witnesses.... would this person still be considered a Christian... or would they be a Muslim... I am assuming they would still be considered a Christian?

littleGizmo wrote: They figured maybe one day when family members pass away and family members grow apart he would offically join Islam in the presense of 3 witnesses....

ovibos wrote: In my opinion, he/she should testify that there is no god but Allah. That makes him/her a muslim already...