But since there were pagan Greeks (multitudes) who accepted Paul's teaching without the scriptures from their infancy, it makes the scriptures irrelevant and unnecessary.
Besides, the OT prophesy is not all that clear-cut, or else the Jews in general would have recognized Christ purely on the basis of their scriptures.
One can argue that perhaps God didn't want them to, so what good is scripture is there is no God-given faith?
While I agree that Scripture isn't *necessary* to accept Christ, it doesn't follow that it is irrelevant. You might be able to kill a deer with a heavy rock. That means a rifle is unnecessary. But I don't think you'd argue that a rifle is irrelevant to such action - it is a different means to the same end.
Besides, the OT prophesy is not all that clear-cut, or else the Jews in general would have recognized Christ purely on the basis of their scriptures.
One can argue that perhaps God didn't want them to, so what good is scripture is there is no God-given faith?
Absolutely it is not clear-cut. And faith is necessary to fully comprehend Scripture. But God can use Scripture to build faith - how many stories are there of people changing in a hotel room after reading Gideon's Bible?