[Lukongsimi]

Thank you for demonstrating that your friend is not being truthful. He claimed that we should acknowledge Muhammad in the Shahada because we are living in his time, and in Jesus's time, we would need to acknowledge Jesus instead. 

However, you mentioned that the Shahada could be modified to include the names of various prophets. I say that the Shahada is a definitive statement that should remain unchanged, as any alterations to its wording would fundamentally alter a core aspect of the faith. 

Who is correct in this matter?

I get a lot of insults from one particular moslem here. He lied and said all kinds of evil things about me just because I wish to remind him of islamic's teachings.

Follow the Bible is correct 
Only moslems follow the Koran 
Only 1 path to reach the Kingdom of God