Verily I say unto thee today, Thou shalt be with me in paradise
The difference is rather important. You see, there are two basic Christian ways of looking at eternal life. 1) You die and your soul pops up to Heaven 2) You die. You're put in the ground. You lie there until Jesus comes again and then your body is resurrected at the last day.
That comma, is the difference. Is Jesus saying today that etc etc, or is Jesus saying that Today etc etc?
Unfortunately the Greek of the time didn't have punctuation as we would understand it and so the entire question of the nature of eternal life is lost to us, because of a lack of commas.
134 years ago this April, the Bulgarians rose up against Ottoman rule. The rebellion was put down with horrid violence. In Bulgaria's second city of Plovdiv 15,000 civilians were massacred. An order was sent by the Ottoman high command to be even nastier to the citizens of Pazardzhik. The order read "Burn the town, not spare it", which would have left 25,000 people dead, or at least homeless. However, a sympathetic clerk who understood the tactical importance of commas changed the command to "Burn the town not, spare it." and thousands of lives were therefore saved from peremptory combustion.
All of which goes to show that a well placed comma can kill, save, or explain the mystery of eternal life.
Would have been burned
P.S. Sir John Harington, top poet and inventor of the first flushing lavatory (which he wrote a poem about), sent a present to James VI of Scotland, just before he became James I of England quoting that passage from Luke: "Remember me when thou comest into thy kingdom."