John of Damascus — on Heb 11:21 (ORTHODOX FAITH 4.11)

“The tree of life that was planted by God in paradise prefigured this honorable cross, for, since death came by a tree, it was necessary for life and the resurrection to be bestowed by a tree. It was Jacob who first prefigured the cross, when he adored the top of the rod of Joseph. And when he blessed Joseph's sons with his hands crossed, he most clearly described the sign of the cross. Then there was the rod of Moses which struck the sea with the form of a cross and saved Israel while causing Pharaoh to be swallowed up; his hands stretched out in the form of a cross and put Amalek to flight;78 the bitter water being made sweet by a tree, and the rock being struck and gushing forth streams of water. Further, the rod of Aaron miraculously confirmed the dignity of the priesthood, a serpent was raised in triumph upon a tree, as if dead, with the tree preserving those who with faith beheld the dead enemy, even as Christ was nailed up in flesh of sin but which had not known sin. … May we who adore this attain to the portion of Christ the crucified. Amen.”