I’m surprised that you’re still using this objection. It is simply not true, as can be seen by checking even leading Jewish translations of the Bible. Those who claim that there are references to a plural servant in Isaiah 53 failed to realize the specific Hebrew grammatical forms being used and consequently mistranslated or misinterpreted the Hebrew text. These objections were answered decisively decades ago.
Readers of English translations of Isaiah 53 might find this argument very surprising. Isn’t the subject of this chapter spoken of throughout in the singular? Well, for hundreds of years now, it has been claimed that there are two words found in two separate verses that hint toward a plural subject: lamo in verse 8 (in the phrase negaʿ lamo, “a stroke for them/him”) and bemotayw in verse 9 (literally, “in his deaths”). It is claimed that these words provide the clue that the singular servant is actually a nation—hence the plurals. The translation of the important part of these verses would then be: “for the transgression of my people [supposedly spoken by Gentile kings; see objection 4.9] there is a stroke for them” (i.e., the people of Israel); “and he [i.e., the servant of the Lord, taken to be Israel] was with the rich in his deaths” (as explained by Radak, the Jews have suffered all kinds of deaths at the hands of their enemies—by the sword, by burning, etc.).
What is wrong with these interpretations? Plenty! First, the phrase negaʿ lamo, as rightly understood by the NJPSV, most likely means that the servant receives a stroke for them—in other words, for those for whom he is suffering. Second, Isaiah elsewhere uses lamo to mean “to it,” not “to them,” (in 44:15: “he makes an idol and bows down to it”). So, even if you wanted to take lamo to refer to the servant (which, as stated, is unlikely), it could still mean “for him” as opposed to “for them.”140 Third, the reason deaths is in the plural in verse 9 is because it is an intensive plural, referring here to a violent death. Such usage of intensive plurals is extremely common in Hebrew, as recognized by even beginning students of the language. Thus, the word for compassion is an intensive plural, rahamim, while the word for God is ʾelohim (see vol. 2, 3.1). More specifically, in Ezekiel 28:8 the prophet declares, “And you [singular] will die the deaths [plural] of one slain [singular] in the depths of the sea” (translated literally). It is difficult to question the meaning here! (See also Ezek. 28:10: “the deaths [plural] of the uncircumcised you will die [singular].”) Whenever the Hebrew Bible refers to the deaths of an individual, it speaks of a violent death.141
You might still be thinking, “I know the idea of two ‘hints’ to a plural-yet-singular servant in this chapter doesn’t make a lot of sense, and your points on the Hebrew grammar seem clear enough. I guess even Jewish scholars and translators agree with you on this. But why don’t the anti-missionaries accept your arguments?” Simple. Old arguments die hard. Still, I think this one is just about to give up the ghost.142
140 The Dead Sea Scroll of Isaiah reads nwgʿ lmw, taken by Semitic scholar Mitchell Dahood to be a passive form (a Qal passive, to be exact), hence, “smitten for them” (see his article, “Phoenician Elements in Isaiah 52:13–53:12,” in Hans Goedicke, ed., Near Eastern Studies in Honor of William Foxwell Albright [Baltimore: Johns Hopkins, 1971], 69–70). This reading completely removes the very basis of this part of the “plural servant” objection. Note, however, that the passive meaning is not assured, according to the scholar of Hebrew and Aramaic Edward Yechezkel Kutscher, The Language and Linguistic Background of the Dead Sea Isaiah Scroll, trans. Elisha Qimron (Leiden: E. J. Brill, 1979). Kutscher explains the anomalous form as a phonetic variation.
141 For the emendation of the text from bemotayw (“in his deaths”) to bamato (“his burial mound”), cf. Blenkinsopp, Isaiah 40–55, 348; see further W. Boyd Barrick, “The Rich Man from Arimathea Matt. 27:57–60) and 1QIsaa,” Journal of Biblical Literature 96 (1977): 235–39, following Ibn Ezra. This, of course, would completely remove the very objection being raised, since the noun would no longer be read as plural.
142 These arguments were already refuted in the nineteenth century by the Oxford Hebrew scholar Eberhard Pusey (see his preface to Driver and Neubauer, Fifty-Third Chapter of Isaiah; this two-volume project was actually Pusey’s idea; see Raphael Loewe’s fascinating prolegomenon to this book for further background). For a popular study, cf. Judy Conaway, The Rejected Cornerstone: Does Yeshua Fulfill the Prophecy of Isaiah 33? (n.p.: n.p., 2001).
Brown, M. L. (2003). Answering Jewish objections to Jesus, Volume 3: Messianic prophecy objections (66). Grand Rapids, Mich.: Baker Books.