Questions to ask someone in a cult.

Start out by asking them this:
"When was your church started?"

Just about every false religion was started by some man or woman withing the last 200 years.  The Catholic Church was started by Constantine in the 4th century.  Have them give you the name of the man or women that is considered to be the founder of their church.  Ask them also what year their church started.

To summarize:
"When did your church start?"
"Who started it?"
"What year did it start?"

Then ask them these 4 questions:

1. Did you know Jesus said in Matthew 16:18 that He would build His church and the gates of hell would not prevail against it.  He has been building His church for about 2,000 years now.

2. Did you know in Hebrews 4 it indicates that Jesus is functioning as the High Priest over His church in heaven.  He has been functioning as the High Priest over His church for about 2,000 years now.

3. Did you know the Bible says in Ephesians 3:21 that God has been receiving glory from His church by Jesus Christ throughout every age, or for about 2,000 years now?

4. Now when did you say your church started again?  After they tell you, ask them this: Well, how could your church be the church that Jesus has been building, functioning as High Priest over, and God has been getting glory from for 2,000 years?

This approach can be used with Mormons, Jehovah's Witnesses, and just about any cult.  I have had Mormons get so confused they just wanted to leave.  From that point you just ask them if they are 100% sure they have a home in heaven.  Then you just proceed to share the gospel with them.

It also might help to know that Baptists have existed from the time of Christ.  They began to be called Ana-Baptists in the 4th century; then in the early 1600s the "ana" was dropped off and we have just been called Baptists since then.  It would help to familiarize yourself somewhat with church history and the history of Baptists.