'Tree of Life' in the Bible

He that has an ear, let him hear what the Spirit says to the churches: To him that overcomes, I will give to eat of the tree of life, which is in the paradise of God.

In the midst of the street of the city, and on each side of the river, was the tree of life, which bore twelve kinds of fruit, and yielded its fruit every month; and the leaves of the tree were for the healing of the nations.

Blessed are those who do his commandments, that they may have right to the tree of life, and that they may go through the gates into the city.

And if any one take away from the words of the book of this prophecy, God will take away his part from the tree of life, and from the holy city; which things are written in this book.