[4:159] And there is none of the People of the Book but must believe in him (Issa) before his (Issa’) death; and on the Day of Judgment he (Issa) will be a witness against them;
Correct belief in Issa (peace be upon him) is a must which is what this verse says. The verse also says that each and every Jew and Christian will believe in him (Issa) before his (Issa’) death. We do not see Jews and Christians with the correct belief and this means that he will have to return for this verse to be accurate. Some argue that “…his death” refers to the death of the Christians and Jews and not Issa (peace be upon him). This interpretation argues that before their death, the Jews and Christians accept Issa (peace be upon him) as they should. This explanation sounds illogical as many die suddenly and do not die a slow and expected death. Such a sudden death leaves no time for a drama style confession or to think and ponder on this matter. If it is argued that they believe while their bodies have died but souls have not departed from this world, it would still be incorrect as the verse states that they will believe before their death. Death occurs when the soul is pulled out. “…before his death” has a singular translated tense and all translators have used it as singular. Had this sentence been regarding the death of Jews and Christians, it would have read “…before their death” (plural) instead of “…before his death” (singular). The literal translation is “…before death” and does not mention “his” or “their” but the translators have unanimously translated it as “…before his death” referring to Issa (peace be upon him). The entire verse is in future tenses which clearly ignores the people of the book already dead at the time of Issa (peace be upon him). Another very interesting interpretation presented is that “him” in “…believe in him…” refers to the Qur’an. However, the context, as seen in previous two verses, shows that “him” here is Prophet Issa (peace be upon him).
Harun Yahya has explained this in some detail:
The expression “and on the Day of Resurrection he will be a witness against them” is important. The Qur’an reveals that on that Day, people’s tongues, hands, and feet (Surat An-Nur, 24:24, Surah Ya Sin, 36:65), as well as their eyes, ears, and skin (Surah Fussilat, 41:20-23), will testify against them. No verse indicates that the Qur’an will be the witness during this event. If the first part of the verse is taken to mean “the Qur’an” – even though there is no evidence in the syntax or the succession of verses for this – “him” or “it” in the second part also would refer to the Qur’an. To accept this, however, there should be an explicit verse confirming this view. However, the commentator Ibn Juzayy does not mention the possibility of the Qur’an being the “him” referred to, and Ibn Juzayy transmitted the views of all the major commentators in his work.
When we examine the Qur’an’s verses, we see that when the same personal pronoun refers to the Qur’an, there is generally mention of the Qur’an before or after that specific verse as in the cases of 27:77 and 26:192-96. If the Qur’an is not mentioned before, after, or in the verse, saying that the pronoun refers to the Qur’an could be mistaken. The verse clearly speaks of the belief in Issa and that he will be a witness for those who believe. Another point we need to make here has to do with the interpretation of “before he dies.” Some believe that this stands for the People of the Book “having faith in Issa before their own death.” According to this view, everyone from the People of the Book will definitely believe in Issa before he or she dies. But at the time of Issa, most of the Jews (who are members of the People of the Book) not only refused to believe in him, but also plotted his death. Then, believing him to be dead, they continued to deny him. In general, the same circumstances are true for the Jews of our own time, as they do not recognize Issa as a Prophet. As a result, millions of the People of the Book have lived and died without ever believing in Issa. Therefore, the verse does not speak of the death of this group, but rather of the death of Issa. In the end, the reality revealed by the Qur’an is this: “Before Issa dies, all People of the Book will believe in him.” When the verse is regarded in the light of its true meaning, several clear facts emerge. First, it becomes apparent that the verse refers to the future, because it speaks of Issa’ death. As explained earlier, he never died but was raised to God’s presence. Issa will return to Earth, where he will live and die like all other people. Second, it says that all People of the Book will believe in him. Obviously, this has not yet happened. And so, given the context, “before he dies” refers to Issa. The People of the Book will see and recognize him, and then become Muslim followers of Issa, as will be explained shortly. In turn, he will be their witness on the Last Day. (God knows best.)
Common sense and logic (plus Hadith) states that it is the future death of Prophet Issa (peace be upon him) and not the death of the people of the book.