Sorry if this has been asked before, but, The Nexus link clearly states that Mithras predates Christ by 400 years with many similarities,
Can the below be proven to have been written prior to the death of Christ?


< Tischendorf's conclusion also supports Professor Bordeaux's
Vatican findings that reveal the allegory of Jesus Christ derived
from the fable of Mithra, the divine son of God (Ahura Mazda)
and messiah of the first kings of the Persian Empire around 400
BC. His birth in a grotto was attended by magi who followed a
star from the East. They brought "gifts of gold, frankincense and
myrrh" (as in Matt. 2:11) and the newborn baby was adored by
shepherds. He came into the world wearing the Mithraic cap,
which popes imitated in various designs until well into the 15th
century.
Mithra, one of a trinity, stood on a rock, the emblem of the
foundation of his religion, and was anointed with honey. After a
last supper with Helios and 11 other companions, Mithra was
crucified on a cross, bound in linen, placed in a rock tomb and
rose on the third day or around 25 March (the full moon at the
spring equinox, a time now called Easter after the Babylonian
goddess Ishtar). The fiery destruction of the universe was a major
doctrine of Mithraism—a time in which Mithra promised to return
in person to Earth and save deserving souls. Devotees of Mithra
partook in a sacred communion banquet of
bread and wine, a ceremony that paralleled
the Christian Eucharist and preceded it by
more than four centuries. >