Since Jesus knows life after death, he could say this on the cross to the repentant criminal executed with him: "Truly I tell you, today you will be with me in paradise" (Lk 23:43). Since Jehovah's Witnesses deny the immediate existence after death, they strive to interpret this verse differently. Adventist Bible translators (see Clear Word Bible) are also bothered that in the other 73 cases, the comma or colon is right after the starting formula ("Truly, truly, I tell you:..."). Jehovah's Witnesses did the same in the New World translation, for the same reason.
According to the Watchtower Society, the dead simply do not exist until the resurrection. Therefore, in their translation, the New World Translation (NWT), Jesus does not promise the good thief that he will be with him in Paradise that day. Instead, it says, "Truly I tell you today, you will be with me in Paradise" (Luke 23:43); the comma is placed after "today" (this phrase, of course, is rendered in 73 other cases with the comma in its usual place). Yet, the comma comes after "… to you," as in all such introductory texts (also in the NWT in 73 out of 74 cases!). From Jesus' perspective, it would have been unnecessary to emphasize that he was saying what he was saying that day.
Another interesting solution is Luke 23:43, which reads:
"...Truly I tell you today, you will be with me in Paradise."
It's interesting to also read this in the Westcott and Hort text. Alongside the Koine language, the Westcott and Hort text contains a literal English translation that, without a comma, reads:
"Amen to you I am saying today with me you will be in Paradise"
Translated (it could be otherwise):
"Verily, I say unto you today, you will be with me in Paradise."
Where should the comma be placed? In the Greek text, it's between the words 'I am saying' and 'today', and in the English translation, it's between 'saying' and 'today' (I tell you, today with me). Accordingly, from the Greek (Westcott-Hort), it can be translated correctly as:
"Truly, I say unto you, today you will be with me in Paradise."
Since 'amen' is a foreign word in Greek as well, instead of 'verily' it would be correct to keep 'amen', but it's not necessary. Even according to the basic text considered authentic and used by the Society, Jesus's promise was not "I am saying today that you will be with me in Paradise someday", but: "I say unto you, today you will be with me in Paradise".
Jehovah's Witnesses immediately argue that there are no commas in the original documents. This is true, so it's up to the translator where to place them (but they should also not forget that there was no lower case 'theos', i.e., god in Greek). But translators do not place the comma as the Witnesses imagine. While there is no translator who is completely unbiased from a theological point of view, they try to push this into the background. In the question of commas and sentence partitioning, they proceed in such a way that they make a decision after examining and based on all similar places in the text to be translated. Jesus uses the phrase 'I say unto you' 74 times. In 73 other cases, 'I say unto you' is separate from the rest of the words. The NWT also translates these places in this way. Only in the case of Luke 23:43 did it proceed differently. So who was really theologically biased?
A few occurrences of the phrase 'I say unto you' in Luke's gospel: 5:24, 7:9, 7:14, 7:28, 7:47, 9:27, 10:12, 10:24, 11:8, 12:4, 15:10, 17:34, 19:26, 19:40, and 23:43. In each case, it is separate from the rest of the sentence.
So what did Jesus want to say? Does John 20:17 contradict this statement?
In John 20:17, Jesus only says that He has not yet gone to His Father. In this case (at most), the thief's place in paradise is not the same as the Father's place.
Another possibility: The Witnesses interpret Jesus's words to mean that they will not be fulfilled literally (Jesus and the thief will never meet face to face). In contrast, the interpretation that the thief entered Paradise that day, while Jesus may have been somewhere else, is more acceptable.
Other Witnesses who admit that the comma is before 'today', argue that the expression 'TODAY' does not always mean the same day. An example of this is the warning given to Adam in Genesis 2: "The day you eat of it, you shall surely die." After Adam ate, he lived for several hundred years. Therefore, 'today' does not always mean 'that day' in the Bible. They also point out that it is appropriate to compare the thief's request with Jesus's answer, and then explain Jesus's consolation in light of this.
Jehovah's Witnesses accuse other Bible translators of being guided by theological bias in their formulation of the text. From this example, it can be seen that the Witnesses' translators were no different. Their theological view led them, even though accepting the correct solution would not necessarily have required them to abandon their doctrine on death.
For Jehovah's Witnesses, it is inconceivable that Jesus would have said to the criminal: "Today (that is, on this day) you will be with me in paradise" (in the intermediate state of the saved). Therefore, the New World Translation renders this verse as: "Truly I tell you today, you will be with me in Paradise." The criminal does not go to paradise (in the intermediate state of the saved) with Jesus that day, but will live forever in the "Paradise on earth" sometime after his resurrection. How do they justify this translation? The biblical lexicon of Jehovah's Witnesses correctly points out that the original Greek text does not contain punctuation marks, and the (later) punctuation depends on the translator's conception. Punctuation, of course, cannot be arbitrary, but must arise from the immediate and full biblical context. Therefore, we must ask two questions: What did Jesus mean to say to the criminal in this place? Then: Where do the punctuation marks belong in parallel or similar places?
The first question: What did Jesus mean to say? Did the evangelist really want to emphasize that Jesus promises paradise life in the distant future to the criminal on the day of their common death? Or did he want to highlight immediate participation in the state of the saved? The latter undoubtedly arises from the context. Because earlier the criminal said to Jesus: "Remember me when you come into your kingdom!" (Lk 23:42). Faith in the last kingdom established by God was widespread among the Jews, in contrast to which Jesus, with unparalleled full power, emphasizes: "Truly, I tell you: today you will be with me in paradise" - even though not yet in the eternal kingdom, yet in the state of the saved between earthly death and the last day. Here, Jesus speaks in the manner of early rabbis about the state into which the souls of the righteous enter at the moment of death, dwelling in paradise, in the gan eden (Garden of Eden, Gen 2:8), without bringing forward the salvation and glory that awaits the resurrected righteous only in God's future kingdom. This interpretation is supported by the contently similar place, Jn 11:23-26. Against Jesus, Martha also speaks of the "resurrection of the last day," which was well known in Judaism. In contrast to this, Jesus opposes the new: "I am the resurrection and the life, he who believes in me, though he die, yet shall he live; and whoever lives and believes in me shall never die." Contrary to the usual end-time expectation, Jesus emphasizes the "here and now," the eternal life that cannot be lost and which believers receive as a gift with his coming. This interpretation - and here we already answer the second question above - is supported by the whole biblical context, especially the other use of the Greek word "semeron" ("today"). It is especially used in the Gospel of Luke. Repeatedly, emphatically at the beginning, it emphasizes the presence of salvation and the Savior: "Today a Savior has been born to you" (2:11). "Today this scripture has been fulfilled in your hearing" (4:21). "Today we have seen incredible things" (19:5). "Today salvation has come to this house" (19:9). This sentence is an organic part of this chain as well: "Today you will be with me in paradise" (23:43). Above all, from the often used phrase "truly I tell you," it follows that "today" belongs to the second part of the sentence, it has to belong there: "Today you will be with me in paradise". For more than 70 times in the New Testament it says: "Truly (truly) I say to you," and not once is "today" added - accordingly, probably not in Luke 23:43 either.
However, in Lk 23:43, the comma / colon always comes right after the "Truly I tell you" starter formula. But why would Jesus have emphasized that he was speaking on that day? Truly I tell you tomorrow... :D ...or I tell you yesterday? :-)
I've listened to plenty of adventist lectures on this, and I must say that their convincing power in the field of biblical studies was very mediocre. I listened through the section where he defends the "truly I tell you today" translation, and I heard absolutely nothing, just reliance on other scripture (Adventist interpretation), general Adventist theologizing, qualification of the opposing position, some enlightenment on church history, but no compelling text-based, linguistic, Greek argument. He didn't say a word about how many times the Bible uses this "truly I tell you today," and what is the unusual "today" for, when there is no need for it. That is, he could not justify textually why the ALL other Bible translations are wrong at this point, the just showed that it does not fit with Adventist theology here. But to call a translation bad at this point, more is needed.
Theology should not define the text, but the other way around. And the text is undoubtedly rounder, more familiar, that "I tell you: today you will be with me."
By the way, paradise is not necessarily identical to heaven. Those who don't go to heaven can still go to paradise. In this case, paradise refers to the place where the righteous of the Old Testament reside after death. "Abraham's bosom" also denotes this place.