early 13c., from O.Fr. devocion , from L. devotionem , noun of action from devovere "dedicate by a vow," from de- "down, away" + vovere "to vow," from votum "vow" (see vow). In ancient L., "act of consecrating by a vow," also "loyalty, fealty, allegiance;" in Church Latin, "devotion to God, piety." This was the original sense in English; the etymological sense, including secular situations, returned 16c. via Italian and French.In old Latin the devotio signified a ritual of self-dedication to the Gods of the Underworld, as Jona Lendering explains:
The ritual itself was simple. The pontifex maximus said the prayer, and the general who dedicated himself repeated it, leaning on a spear, and dressed in a toga. With the toga over his head ("Gabine fashion"), the commander rode to the enemy. If he survived, he was never to perform religious acts any more; if an ordinary soldier had dedicated himself to the Underworld and had survived, a statue with a height of seven feet had to be buried instead. One such statue has been excavated in the country of the ancient Vestini, at Capestrano in the Abruzzi.
When Rome became a monarchy, the word devotio was used to describe the self-sacrifices for the well-being of the emperor. A notorious example is the story of Publius Afranius Potitus, who promised to commit suicide if only the emperor Caligula would recover from an illness - the emperor insisted that the man would indeed descend to the Underworld.Lendering mentions Greek antecedents (notably the story of King Leonidas at Thermopylae), and suggests Carthaginian King Hamilcar's death at Himera in 480 BCE while making an offering to Poseidon was a similar sacrifice. What seems clear is that this myth and this kind of ritual/ritualized death for one's community was likely found throughout the Mediterranean and much of Levantine. The "cinctus Gabinus" described above was associated with sacrifice and worn by Roman emperors in their office as high priest. And according to scholar Andrew Feldherr:
The enemy are afflicted with terror wherever the consul rides, and when eventually they kill him, their fate is sealed. The consul’s body is always buried under the thickest pile of weapons and corpses and so cannot be found until the next day.
How many of these details accurately reflect early Roman religious practice remains uncertain. The idea of charging a man or beast with the impurities of the people and sending it off to exert its destructive influence among the enemy possesses many analogues, from Hittite sacrificial practice to the legend of the Trojan horse. However, Versnel has argued that what has become the archetypal form of devotio actually evolved from the more widespread but somewhat less dramatic practice of invoking the gods’ power by making over to them the lives and property of the enemy. But whatever the actual authenticity of Livy’s description, the act clearly possesses a special significance for his text. The historian explicitly justifies his inclusion of the details of the ritual in terms that remind us of one of the cardinal aims of his history: he has preserved the tradition of an archaic Roman practice into an age when native religion has been supplanted by foreign ritesIn time "devotion" came to be a synonym for the zeal and ardent desire required to offer oneself up in such fashion (Classical Latin used the word studium to describe such eagerness - and yes, that is related to studere and our English "student." Medieval Latin lost that distinction). "Devotionals" provided a way by which one could bring the sacred into one's daily life through meditation and prayer. "Devotees" came to mean enthusiasts, not sacred vessels cum spiritual bioweapons.
Within that meaning-slippage we can see many of the changes between the pre-Christian and Christian worldviews. Even before putting on the cinctus gabinus the devotio was one set apart, one who is not only willing to die for the Gods but willing to die at their hands. The devotio offers up body and soul for the tribe, striking a deal in order to preserve the nation and community. It is a perfect offering, one which gains its power by its terrible price.
Christian models for devotion preserved that idea of self-sacrifice but wiped out nearly everything else about the ritual. The office of devotio was subsumed into the new office of "martyr" but that crown was reserved for those who died for Christ. Those who fought for other Gods were devil-worshippers and fanatics whose bravery was a sign not of their goodness but of their innate bestial corruption. Studium, zeal, became the new ideal: the interior life became more important than the outward sign of the consul wearing the trappings of the scapegoat.
(As an aside: It's not for nothing that the Christians also pushed for monopolistic control on outward signs of the Divine, or as they called them, sacraments).
This is not to say that the use is "wrong." I'm hardly arrogant enough to think I can erase two millennia of lexical history. Nor would I deny that there has been much good, as well as much evil, done in the name of Christian devotion. But I think it may behoove us to consider again the majesty and terror of the cinctus and the spear and the holy words by which one gives up everything so that your people might live. It might help us to remember the difference between those things which we deeply enjoy and those things we might be willing to die for.