In your opinion what causes christians to believe in Jesus

[Sheldon]

Are you a Seventh-day Adventist?

Yes, I think I've mentioned it in other threads

"the Seventh-day Adventist Church generally believes in a young earth, typically estimated to be around 6,000 years old. This belief is rooted in a literal interpretation of the Genesis creation account and the writings of Ellen G. White, a co-founder of the church. While the Bible doesn't explicitly state the age of the earth, Ellen G. White's interpretations and writings have shaped the church's understanding and belief."

If the universe is only 6000 years old, how is light visible from stars, that are billions of light years from the earth?

Maybe a deity created the light en route, just to confuse us. 

Good reasons to believe something, would not in my opinion, include denying objective and irrefutable scientific facts, but hey that's just me.