All Christians believe that
baptism by water is essential to
the administration of the
sacrament.
John 3:5
Jesus answered (Nicodemus), "Amen, amen, I say to
you, no one can enter the kingdom of God without being
born of water and
Spirit."
The Catholic Church believes
that a "washing of the body
with natural water" is what
is required for valid baptism.
Matthew 28:19
... baptizing them
in the name of the Father, and of the
Son, and of the holy Spirit,