Hi bling,
Well, these people may not be ready, or may never be. We do need to consider that when Jesus, the Son of the living God that Israel claimed to believe in got to the day of the cross, the evidence shows that although he and his disciples had spent some 3 years criss-crossing all of Isreal, there were very few who believed in him. The picture we are given is that the great crowd assembled before Pilate cried out for Barabbas. Except for maybe a few Roman centurions, that great crowd was Jewish.
We also need to remember that Jesus' own words were that few there be that find the way to eternal life. The Scriptures even paint a picture that a lot of christians are going to be turned back also. So, keep up in prayer and always seeking the Holy Spirit to be with you when you share God's word with them, but be careful that you don't let a small harvest disappoint and discourage you.
God is real and God is good. For the born again believer all that we know about God comes to us through the Jewish Scriptures. That's why still today, Israel is known as God's people. God has rebuked them and disciplined them, but God has never wholly turned aside from being their God. Similarly, we do need to understand that sharing the gospel is not always successful, and many times bears fruit at some later date. You are planting and someone else may come along and water, but it is God that makes our faith grow.
When you say that you talked about that, how deep did you go? Did you cover the prophecy that God gave to Daniel? Did you cover the prophecy given to Hezekiah? There are some prophecies that are much more forceful than others, and often times more specific so that someone doesn't say, "Well, that may or may not be a prophecy in how it was fulfilled". I've often found the prophecy of Daniel to be a powerful prophecy and it is very specific in even mentioning that it is regarding the Messiah.
I've told people before of the prophecy that the virgin shall be with child, and sometimes the response to me is, "Oh, in those days in Israel every woman wanted to be a virgin with a child and somebody finally pulled the wool over the people's eyes". Are you familiar with the prophecy given to Daniel and how best to explain it?
Here are some sites that you might want to read over to hone your skills in presenting this prophecy:
The Messianic Time Table According to Daniel the Prophet • Jews for Jesus
Daniel's Prophecy of the Seventy Weeks
I also find it appealing to look up the prophecy in Isaiah that Jesus spoke of in his first adult visit to the temple. It's also a powerful prophecy and is even more so because Jesus declared to all those in attendance that he was fulfilling the prophecy right now before their very eyes. Then, as the gospel accounts unfold...Jesus did! He did heal the sick and bind up the lame. He did give sight to the blind and spent some three years proclaiming the day of the Lord.
So, as I say, I would think that the greatest argument against the faith of the Jewish Scriptures being some sort of superstition, is to show how the prophecies seem to have been fulfilled and that's not likely to happen for some superstitious belief. A black cat crossing one's path is a superstitious belief and if we had a couple of dozen prophecies that declared before a black cat crossed someone's path and a written account before the event that what turned out bad was foretold to turn out bad, we likely wouldn't think of black cats crossing our paths as just superstition.
God bless,
In Christ, ted