You as a Christian have an answer you are trying to confirm. I have no answers and am looking for truth. In my world when you suggest that God is merciful and loving yet sends people to hell...that sounds like a contradiction. How can you make such a claim?
How do you respond to Susan? What is your natural inclination? Perhaps for many the tendency is to respond like this Christian teacher:
Students: How do you know that Jesus really did that?
Teacher: Because it's in the Bible!
Students: How do we know that the Bible is true?
Teacher: Because God gave it to us!
Students: How do we know God gave it...
Teacher: Enough Mr. Johnson!!
Now, let's consider the answer Jesus gives to someone asking questions. Nicodemus came to Jesus with some questions and Jesus spent some time giving him answers:
Rabbi (Jesus), we know that you are a teacher from God, for no one can do these signs that you do unless God is with him. Jesus answered him, 'Truly, truly, I say to you, unless one is born again he cannot see the kingdom of God. Nicodemus said to him, 'How can a man be born when he is old? Can he enter a second time into his mother's womb and be born? Jesus answered, 'Truly, truly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God. That which is born of the flesh is flesh, and that which is born of the Spirit is spirit. Do not marvel that I said to you, 'You must be born again.' The wind blows where it wishes, and you hear its sound, but you do not know where it comes from or where it goes. So it is with everyone who is born of the Spirit' (John 3:1-8).Notice a few things about this conversation. First, Jesus did not just give rehearsed cliches as answers. He took the time to explain the truth and even used a metaphor to instill truth into Nicodemus. Second, it is clear that Jesus and Nicodemus are having dialogue and it is simply not just a debate.
Nicodemus left this encounter still as a non-believer. Later in the Scriptures we do read that He came to faith in Jesus trusting Him as his personal savior. I have to believe that similar conversations went on between Jesus and Nicodemus until he crossed that threshold into faith. So, as believers follow the example of Christ let's go find some people to have genuine dialogue with about the truth as revealed in the Scriptures. If you are one given to debate every time someone questions a truth claim about the faith then remember this saying, "You may win the battle and lose the war." That is you may win the argument but lose the relationship with that person.