The Wood of the Cross
Which tree was used to make the cross? Legend and folklore have many strange answers.
When Adam was dying at the age of 900, he sent Eve and their son Seth back to Eden to beg the angel guarding the entrance for the oil of mercy to anoint him in his illness. St. Michael appeared to them, saying it was time for Adam to die, and the oil could not be obtained until the crucifixion. Instead, he gave Seth wood from the Tree of Knowledge of Good and Evil, and said that when that wood flowered, Adam would be saved. From this wood came the wood of the cross, and at the crucifixion it bloomed.
In another version of the story, St. Michael gave Seth three seeds from the forbidden fruit and told him to place them under his father’s tongue when he was buried. From these seeds grew a cypress, an olive, and a cedar tree which were all eventually used to make the cross.
These early legends, later incorporated into medieval versions of the pseudepigraphal Life of Adam and Eve and other texts, are part of a strong tradition identifying the wood of the tree of Eden with the wood of the cross.
In some stories, the cross was made of wood the grew from the staff of Moses or the rod of Aaron. In one elaborate version, it was wood from the garden of David which Solomon intended for the Temple in Jerusalem. The workmen, however, were unable to cut the wood, so Solomon ordered them to bury it. The Pool at Bethesda was built over the site of the burial, and on Palm Sunday Solomon’s buried trees floated to the top and were subsequently used for the cross.
In a similar tale, when the Queen of Sheba visited Solomon she refused to walk over a footbridge because she had a vision that it was built from the wood of paradise. She told Solomon to guard it carefully because one day the world would tremble before it, whereupon the bridge sank into the water, only to float to the surface during Holy Week.
Preaching About the Cross
This kind of connection between Adam and Christ, or David and Christ, was a popular theme for preaching from the early days of the church, and became very prominent in the middle ages, allowing preachers to link and Old and New Testaments. St. Thomas Aquinas, for example, links Adam and Christ in several places:
The human race is wounded by wood, because the first man ate from the forbidden wood and therefore the divine Wisdom found the medicine from wood. The human race is wounded because of disobedience, since the first man stole a fruit from the forbidden wood. The new man has placed himself, as a salutary fruit so to speak (quasi), back onto the wood. The Psalmist says: “Did I pay what I have not stolen?” He has given himself back to the wood, so that he would recompense the injury and bring the remedy. Hence we read in Wis 14:7: “Blessed the wood by which justice comes about.”1
St. Thomas was very skeptical about the literal truth of apocryphal legends, but saw utility in their figurative senses. He found the type of wood less important than the form: the cross points in four directions to symbolize Christ’s power over the four corners of the earth. In this, he was following Augustine, Chrysostom, and others, who explored the deep symbolism of the cross. In particular, he was interested in the “four parts” of the cross indicated by Augustine in his Tractates on John:
The Breadth: The crossbeam, where the hands are affixed. It symbolizes good works, because the hands are stretched out in action.
The Length: The upright to the crossbeam, where the body is extended. It symbolizes long-suffering or perseverance, because it endures until the end.
The Height: The upright above the crossbeam, where the head is placed. It symbolizes the hope of those who look toward things above.
The Depth: The part in the ground, which is concealed. It symbolizes the depth of God’s grace, which is unsearchable and supports the entire structure from a hidden source.
The Wood
The influence of Augustine’s interpretation eventually caused to the three seeds in the story being increased by one, allowing for four woods from which each part of the cross was made. This led to a medieval saying: Ligna crucis palma, cedrus, cypressus, oliva. (The woods of the cross are palm, cedar, cypress, and olive.) Each symbolized something in particular.
Palm for the crossbeam (victory): The palm is the symbol of victory and triumph. By placing the palm at the hands of Christ, the legend suggests that even in the act of being bound and executed, Christ was winning a victory over death. It represents the “spoils of war” taken back from the devil.
Cypress for the upright (virtue): Cypress is known for its height and its powerful, sweet fragrance. It symbolizes the sweet odor of virtue and the uprightness of Christ’s life. In some traditions, it also represents “death” (as cypress trees were often found in cemeteries), but death transformed into a “pleasing sacrifice” to God.
Cedar for the base (incorruptibility): Because cedar resists rot, it represents the incorruptibility of Christ’s divinity. Just as the cedar base supports the entire weight of the Cross, Christ’s divine nature is the hidden foundation that supports His human suffering.
Oliver for the titulus (peace): The olive branch is the ancient symbol of peace and mercy reaching back to Noah’s Ark. Placing it at the head of the Cross signifies that Christ is the “Oil of Mercy” promised to Seth. It represents the end of God’s wrath and the reconciliation between Heaven and Earth.
Tree Lore from the Cross
While theologians and preachers developed nuanced ways of preaching the cross, folklore and superstition also took a hand. One of the most famous stories is about the aspen tree. When the wood of the cross was being chosen, all the trees bowed in shame and refused to be used, except the prideful Aspen. As a result, it was cursed to tremble forever, even in the absence of a breeze, in a state of perpetual fear and guilt. This is an etiological myth to account for the trembling of aspen leaves, which have flattened stalks set at right angles to the left blade, making them flutter in the slightest breeze.
Likewise, mistletoe was believed to have once been a mighty tree, but after being used for the cross it was so ashamed it shrank away and became parasitic. Similar versions of the story account for the dwarf-birch, among other regional variants. Willows weep because they were used for the cross. The strawberry’s tree turned red after it was stained with the blood of Jesus.
The drops of resin leaking from pine are the tears it sheds for its use as the cross. The leaves of the white poplar are dark green on top and bright, silvery-white on the bottom. It is said that the leaves turned white on one side from the pale reflection of Christ’s face as He looked down toward His feet.
Boxwood is dense and heavy because of its sorrow. It’s dangerous to sleep under the deadly shadow of walnut tree, which emits a poison because it was used for the pegs that held the cross together. (Walnut trees do, in fact, “poison” the soil to kill off competitors for water and nutrients. The phenomenon is called called allelopathy.)
A person is safe sheltering under an elder tree in a storm because lightning would never strike the tree from which the cross was made. If an elder planted on a grave eventually flowers, the person buried there is in heaven. Because of the connection with the cross and elder, there are places where people would not burn them for fuel even if they had no other wood.
All of this folklore and superstition develops organically, as stories are handed on from the generation to the next to explain the numinous quality of the world around them. They are a beautiful testament to the deep piety of people who saw Christ in everything.
Thomas Aquinas, “Sermon 18: Germinet Terra,” in The Academic Sermons, trans. Mark-Robin Hoogland, vol. 11, The Fathers of the Church: Mediaeval Continuation (Washington, DC: The Catholic University of America Press, 2010), 272.
The "tree used for the cross was punished by being made small" variant I am familiar with is the dogwood.
The Seth legend is extraordinary — seeds placed under a dead man's tongue, flowering into the instrument of salvation. That's the kind of liturgical recursion that medieval imagination did better than anyone. The four-wood symbolism growing out of Augustine's four-part cross is a perfect example of theology generating mythology.