The eight-pointed star is the Star of Redemption or Regeneration and represents baptism. Eight is traditionally the number of regeneration, and thus many baptismal fonts have an octagonal base.
Providing added significance is the assumption that Jesus was circumcised and named when he was eight days old (the traditional Jewish practice); baptism is seen as the New Testament equivalent of circumcision.
Finally, eight persons were saved in Noah's ark, which is another Old Testament
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