John 11.25-26:
Jesus said to her, “I am the resurrection and the life. Whoever believes in me, though he die, yet shall he live, (26) and everyone who lives and believes in me shall never die. Do you believe this?” (ESV)
The statement quoted above was made by Jesus to Martha, a sister of Lazarus, just before Jesus raised Lazarus from the dead. It means that whenever a believer in Jesus dies, he or she doesn’t cease to exist. The Apostle Paul also confirmed that to die here on earth results in being present with Christ. In Philippians 1.23 he writes: “I am hard pressed between the two. My desire is to depart and be with Christ.” (ESV)
When Jesus made the statement to the thief on the cross: “Truly I say to you, today you will be with me in Paradise” he affirmed that the truth set forth in all the verses above will be applicable to this thief. And we have the word of Jesus on this that whenever a believer in Jesus dies, he or she will immediately be in Paradise with Jesus. For the thief, it was going to be that very day.