There were a number of deities within the Greek pantheon who are often regarded by modern scholars as mere personifications–deities bearing the names of concepts, such as Nike (Victory) or Tyche (Fortune). This is almost never the case (although as a believer I may be biased!); many of these deities have their own stories, or received their own prayers and offerings from worshippers.
And the Greek goddess Eleos, whose name may be translated as Mercy, Pity, or Compassion, was no mere personification.
In ancient Greece there was a tradition of the altar as a place of refuge.
This is not a foreign concept to us; we are familiar with the concept of seeking sanctuary within a church. In fact, the very word “sanctuary,” meaning refuge, is also a term for the most sacred area of a temple–that is how connected the one is to the other. What many are less familiar with is that this concept predated Christianity by centuries.
As with many things, the theory and the practice may have sometimes conflicted. In theory (and according to various legends) the protection of suppliants was a sacred duty and interfering with it was not only a disgrace but a sacrilege, and the gods would punish any who did so. Practically and politically speaking, however, this was not always the case. If a temple was protecting an enemy of the city, the citizens might be less likely to respect that person’s right of asylum; similarly, if you were in trouble at home and went to a temple in the next town over to seek refuge, you might be endangering those who were protecting you.
And certainly some temples were in a better position than others to provide such protection. A large temple that received many visitors as a matter of course would have better facilities for caring for suppliants. A temple in a remote area might also provide protection due simply to its remoteness. The altar of Eleos, however, was quite urban.
The Altar of Eleos in Athens may have also been known (according to a number of scholars) as the Altar of the Twelve Gods (presumably the dodecatheon of Athens–Zeus, Hera, Demeter, Poseidon, Athena, Apollo, Artemis, Hephaistos, Ares, Aphrodite, Hermes, and either Dionysos or Hestia) a name similarly well-known as a resource and destination for suppliants. While the identification of the Altar of the Twelve Gods with the Altar of Eleos is uncertain, Eleos’ altar is first attested in the second century CE while that of the Twelve Gods was installed in 522 BCE. It may be that over time the altar became associated with the goddess of mercy because of its history as an altar of supplication.
In any case, the existence of an altar to a divinity of goodness and compassion was at the time regarded as a mark of Athens’ own goodness and compassion as a city.
Eleos welcomed and received all who came to her; she accepted all offerings. It was said of her altar that “the wretched made it sacred.” She was and is a good and gracious goddess, well worth worshipping despite her lack of a personal mythos.