According to Maltese legend, a local tree was struck by lightning many years ago, and changed in appearance. Its contorted bark metamorphosed into an image of Jesus hanging from the cross.
Although the Catholic Church officially recognizes miracles, it has declared that these types of apparitions are no longer worthy of "public revelation."
The issue of public vs. private revelation has been a contentious one for the Church, but was recently clarified by the current pope, Joseph Ratzinger. Ratzinger declared that public revelations (essentially big, flashy miracles), ended with the death of the last living Apostle in 100 A.D.
Apparitions, even though officially recognized by the church, are now deemed to be "private revelations," which means one doesn't have to believe in them. Such revelations are binding on whoever has them, but not upon all Catholics.
Of course, for non-believers the tree is neither public nor private revelation, but rather an example of the psychological phenomenon of pareidolia, the perception of meaningful significance in a meaningless, random stimulus. Regardless of religion, these sorts of images of Jesus, Mary, the name of Allah, or a Singaporean monkey god, continue to appear in the oddest of places, and to intrigue the faithful.
The Jesus Tree of Malta is located right off the main road from Zebbug to the walled city of Mdina, the former home of the Knights Hospitalier.