See on Nazarene, Mat 2:23. Root is a sprout from the root.
He that shall rise to reign
Rev., that ariseth to reign. Literally from the Septuagint. Ariseth to reign is a paraphrase of the Hebrew stands as banner. Bengel says: “There is a pleasant contrast: the root is in the lowest place, the banner rises highest, so as to be seen even by the remotest nations.”
Shall - hope
So Septuagint, which is a free rendering of the Hebrew seek or resort to.