  We report the discovery and spectroscopic identification of the bright doubly
lensed quasar eRASS1 J050129.5-073309 at redshift $z=2.47$, selected from the
first all-sky survey of the ${\it Spectrum\; Roentgen\; Gamma\; (SRG)}$ eROSITA
telescope and the ${\it Gaia}$ EDR3 catalog. We systematically search for
extragalactic sources with eROSITA X-ray positions having multiple ${\it Gaia}$
counterparts and have started spectroscopic follow-up of the most promising
candidates using long-slit spectroscopy with NTT/EFOSC2 to confirm the lens
nature. The two images are separated by $2.7''$ and their average ${\it Gaia}$
${\it g}$-band magnitudes are 16.95 and 17.33. Legacy Survey DR10 imaging and
image modeling reveal both the lensing galaxy and tentatively the lensed image
of the quasar host galaxy. Archival optical light curves show evidence of a
variability time delay with the fainter component lagging the brighter by about
100 days. The fainter image has also decreased its brightness by about 1
magnitude since 2019. This dimming was still obvious at the time of the
spectroscopic observations and is probably caused by microlensing. The optical
spectroscopic follow-up obtained from NTT/EFOSC2 and the evidence provided by
the imaging and timing analysis allow us to confirm the lensed nature of eRASS1
J050129.5-073309.
