It is not clear as to what the mechanism God uses to harden hearts is; allowing such or in someway forcing such. It would be easy not knowing why God would want such for us to have difficaulty with this passage. With such passages it is best to give God the bennefit of our doubt and seek through for a more understandable why.
Why? Hearts tend to harden or soften on their own given situations whether reasonably our unreasonably. These peoples hearts had been hard and continue to be unreasonably hard to this day. Perhaps God knowing that their hearts would not soften (or only temporarily) set in motion the final hardening (atleast for this time). Neither do we know the demonic warfare occurring behind the scenes that God may have been cleansing out of the area.
Many believe that since the temple destruction AD70 and resultant worldwide dispersion of the Jews that we have now lived in an "time of the gentiles" era. With drawing of the Jews back to Jerusalem since 1948 we now see a signal of the closing of the age and the drawing near of our redemption; The Lord's second coming. There are others that say that this all happened AD70 and that the Lord has already returned. Some believe that none of this happens until the end of the world. I believe that kjv@Luke:21:24 is the key verse suggesting the dispersion/age interpretation, "be led away captive" I have yet to find evidence of in other end time prophecy.
I sense the suggestion that before creation the plan was all laid out, Jesus was to be our redeemer. Wisdom became all that which moved that plan forward, the establishment of the covenant, the law, Israel, the prophecies, the conviction of the Holly Spirit. Wisdom was there when all these essential things were framed, it is there evident in all creation revealing even the Godhead so that we are without excuse kjv@Romans:1:20. Wisdom is the purpose and direction and establishments leading all men back to their savior.
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