  We discuss the physical nature of a remarkably faint pair of Lyman
alpha-emitting images discovered close to the giant cD galaxy in the lensing
cluster Abell 2218 (z=0.18) during a systematic survey for highly-magnified
star-forming galaxies beyond z=5. A well-constrained mass model suggests the
pair arises via a gravitationally-lensed source viewed at high magnification.
Keck spectroscopy confirms the lensing hypothesis and implies the unlensed
source is a very faint (I~30) compact (<150 pc) and isolated object at z=5.576
whose optical emission is substantially contained within the Lyman alpha
emission line; no stellar continuum is detectable. The available data suggest
the source is a promising candidate for an isolated ~10^6 solar mass system
seen producing its first generation of stars close to the epoch of
reionization.
