I recently met a young homeless man who’s had a very rough life. He started a conversation with me, and eventually I asked him if he knew Jesus. He said that he lost his faith when he was about 18 because his life went downhill, but when he is lonely, he feels Jesus is the only one he can talk to. We arranged to meet together every week. How can I share the Good News with him? I don't ever know what to say when I talk to people like this about the gospel, but I feel the Lord calling me to do it anyway.
It’s great that God has given you this new relationship. I encourage you to pursue it. I’d say to pray daily for him and especially for your times together. Feeling a bit uncertain is good in that it encourages dependence on the Holy Spirit, which is exactly what you need when sharing the gospel.
That he says he talks to Jesus is good, but he needs to embrace the good news of Jesus to be on speaking terms with Him, otherwise his sin will get in the way. Once there’s repentance and confession of sin, then he’s free to talk to Jesus about anything and everything—if God be for us, who can be against us? (Romans 8:31).
Here are some resources that might be helpful for developing a Christ-centered and gospel-oriented relationship with him:
Also, here are some short but right-on gospel videos you could show him on a tablet or a phone. You could watch them together and ask him what he thinks and what questions he has. You could actually go through all of them, or pick one or two. Or, one each time you meet with him to let it soak in slowly:
I’m praying that God would use you to clarify the Good News and also to help you grow in your walk with Jesus by serving Him and this needy man.