What Do You Say When They Say…
I can’t consider Jesus because the prophecies that you say describe Him are all talking about someone or something other than the Messiah. Isaiah 53 (actually 52:13-53:17) refers to Israel. The word you point to in Isaiah 7:14 is technically not “virgin” and Psalm 2 where it talks about God’s son is really referring to King David or the Land of Israel.”
The fact of the matter is, there are answers to each of these objections. But judging by the way the statement is framed, the person wouldn’t accept your answers, but would merely give more examples of why he or she cannot believe in Jesus. You have to realize that these probably are not real questions where the person is looking for an answer. They are basically objections or excuses. If you provide a reasonable answer and the person is able to admit that your answer makes sense before raising another question, then it is worth your time to research and answer other issues he or she may raise. But if you get an impatient sounding, “Well, I don’t know about that, but what about this….” you are dealing with roadblocks, not real opportunities.
When a young man asks a pretty young woman out on Saturday night and she tells him that she has to wash her hair, he should get the idea that she simply doesn’t want to go with him. Any woman who wanted to go out with the young man would arrange to wash her hair earlier or later. But if he keeps asking, each Saturday there will be a different reason, or maybe even the same reason. Should he change the day to Sunday or Friday, she just has to become more imaginative with her excuses. As long as she does not want to go with him, she will find a reason not to do it.
When Jewish people don’t want to go with Jesus, they find reasons not to do it. They’ll either find fault with the texts, find fault with Christians (e.g. anti-Semitism, the Holocaust) or plead utter ignorance. Yet there are Jewish people who are willing to consider the gospel seriously. So how can you tell if someone is giving you an excuse or an honest objection? You can ask a question of your own: “Do you mean that if I can give you a reasonable explanation of _________ (such as why Isaiah 53 speaks of the Messiah, and not Israel) that you would be willing to ask God to show you the truth about Jesus? And if He shows you that Jesus is the Messiah, you would have the courage to take a stand for Him?”
When you ask the question, always give the person a way to escape. God doesn’t drive people into corners (a notable exception might be Jonah). In general He presents His good news as an opportunity to which people can respond. Let people back away if they want, and then use the powerful secret weapon that God gave you. That weapon is prayer.