Why are you convinced there is life after death? As far as I'm concerned, this life is all there is, and once it's over that's the end. But I'm open to any proof you might have, because I admit I wish I had something to look forward to. — M.McK.
I am convinced there is life after death for one reason: Jesus Christ died and was placed in a tomb—and two days later came back to life.
Think about it a moment: What would it take to prove to us that there is life after death? The answer is clear: Someone would have to die, and then come back to life again. It wouldn't be enough for them to have a so-called "near-death" experience; their death would have to be real. And it wouldn't be enough for only one or two people to see them; it would require many witnesses.
But has this ever happened? Yes—when Jesus Christ rose from the grave! His death was real; hard-bitten Roman guards made sure He was dead before they took Him down from the cross. And His resurrection was real also, because hundreds saw Him during the next forty days. Paul, writing over 25 years later, noted that "he appeared to more than five hundred of the brothers at the same time, most of whom are still living" (1 Corinthians 15:6).
How could this happen? It happened because Jesus Christ was not just another man. He was God's only Son, sent from heaven to save us from our sins. Only He could say, "I am the resurrection and the life. ... Whoever lives and believes in me will never die" (John 11:25-26). This can be your hope, by giving your life to Christ today.