The great Jesse window in Chartres cathedral was one of the great influences in my conversion to Christianity in 1984. Studying the window, among many other great 12th and 13th century gothic works, the craftsmen of that age communicated the faith to me and I was suddenly aware of an essential Truth of life that I had never seen before: the Incarnation was the key to the whole mystery of life. The Jesse tree shows the roots of Jesus in the Jewish Bible.
And there shall come forth a rod out of the root of Jesse, and a flower shall rise up out of his root.
In that day the root of Jesse, who standeth for an ensign of the people, him the Gentiles shall beseech, and his sepulchre shall be glorious.
Now shalt thou be laid waste, O daughter of the robber: they have laid siege against us, with a rod shall they strike the cheek of the judge of Israel.
For I say that Christ Jesus was minister of the circumcision for the truth of God, to confirm the promises made unto the fathers. But that the Gentiles are to glorify God for his mercy, as it is written: Therefore will I confess to thee, O Lord, among the Gentiles, and will sing to thy name. And again he saith: Rejoice, ye Gentiles, with his people. And again: Praise the Lord, all ye Gentiles; and magnify him, all ye people. And again Isaias saith: There shall be a root of Jesse; and he that shall rise up to rule the Gentiles, in him the Gentiles shall hope. Now the God of hope fill you with all joy and peace in believing; that you may abound in hope, and in the power of the Holy Ghost.
And I saw in the right hand of him that sat on the throne, a book written within and without, sealed with seven seals. And I saw a strong angel, proclaiming with a loud voice: Who is worthy to open the book, and to loose the seals thereof? And no man was able, neither in heaven, nor on earth, nor under the earth, to open the book, nor to look on it. And I wept much, because no man was found worthy to open the book, nor to see it. And one of the ancients said to me: Weep not; behold the lion of the tribe of Juda, the root of David, hath prevailed to open the book, and to loose the seven seals thereof.