Nay. Verily, ye do err, not knowing the scriptures, nor the power of God. Yet, for this very cause it is so written, Behold, a virgin shall conceive, and bear a son, and shall call his name Immanuel. And she shall bring forth a son, and thou shalt call his name JESUS: His eyes were as a flame of fire, and on his head were many crowns and he had a name written, that no man knew, but he himself.
This has to be talking about some other man named Jesus and not Jesus Christ, because Jesus died on the cross and rose again on the third day. He was God in human form who came down as a man, a perfect man there was no sin in him. Jesus came for one purpose and that was to be the supreme sacrafice. Jesus did not marry, nor did he have children, so there is no way he could have had grandchildren.
God wouldn't have told us not to take away his words if he didn't know we would do it. He wouldn't have told Eve and Adam not to eat the fruit if he didn't know they'd do it.
We often hear, God knows my heart but God does know we don't until we read God’s word and find out about our heart. When we do there can be a change in us if we take it or embrace God’s word to ourselves.
I believe it should have been left in the Bible, God's word is God's word, and none can change it, Isaiah 28:9- 12, for those who are sincere, in heart will get His understanding.