Question: How does a believer in Christ convince a member of another religion that their scriptural texts are false and the Bible is true, when their texts claim truth and they see the Bible as fallacy?
Answer: First of all, if any convincing happens, it will be done by the Holy Spirit. It is the Holy Spirit who draws people to Jesus Christ. Still, it is our responsibility to communicate the Gospel as clearly and compassionately as possible. With that in mind, we can direct them to works by Lee Strobel and Josh McDowell that chronicle their journey from unbelief to belief. Their personal testimonies combined with their intellectual pursuits are convincing.
The best thing you can do is to live the Gospel in front of your friend and pray for an opportunity to share. Then, when the opportunity arises, be ready to share. Know that this may take years. And that’s ok. Also, don’t forget that it isn’t your job to convince anyone of anything. Your job is to be available to the Holy Spirit.