Sometimes the fish symbol has the Greek letters ΙΧΘΥΣ in it. This is just the Greek word for "fish" (see Strong's Greek #2486). Some people though have made use of the letters of the word as an acronym for a clever phrase.
The symbol of the fish is also found in the miter the Pope wears. (See the fish in the side view?)
As for Christ on the cross, the oldest artistic representations of the Christian cross
depict a figure of a lamb (Aries).
The practice of symbolising the saviour by a lamb continued until the Council of Constantinople
(692 CE) under the pontificate of Agathon and during the reign of Constantine Pogonat. It was decreed
that, instead of the ancient astrological symbol of Aries the lamb, all crosses depicted in art should be
combined with the figure of Jesus. The retiring of the Lamb as the main Christian symbol, translated from
the Latin, is as follows:
|In the Roman Sotteranea of Antonio Bosio, concerning the image of Christ under the figure of a lamb:|
|In certain representations of the images of the saints, a lamb is portrayed. We, therefore,
accepting the old forms and shadows as signs of the truth and as traditional symbols of the
church, prefer Grace and Truth, which we accept as the fulfilment of the Lamb. So, that
which is perfect, let us place in pictures, even before the eyes of all. We have decreed that
the Lamb, which taketh away the sins of the world, Christ our God, ought to be portrayed
henceforth in human form in place of the Lamb.|
(Higgins, Anacalypsis, Vol.2, pp.111-112)
At first, Jesus was represented fully robed, standing calmly before the cross with outstretched
arms. The lamb continued to be shown, usually at the foot of the cross. Later, the figure of Jesus was
placed on the cross, undraped, bleeding and tortured by pain from wounds, as he is represented on
crucifixes today. Pope Adrian I confirmed this point.1
12. Due to earth's precession the Sun is now in Pisces the fish on the Vernal Equinox.
[A fish is now the symbol of Christianity.]