The Southern Fish depicts the people of God receiving the water of life from God. It lies directly under Aquarius, and the ancient celestial Stream ends exactly in its open mouth — in the bright star Fomalhaut, whose Arabic name literally means 'mouth of the Fish'. Therefore the Southern Fish is close in meaning to the constellation Pisces, but does not merely repeat it: Pisces shows two peoples of God — Israel and the Church — bound together, whereas the Southern Fish shows the people of God as one whole, directly receiving the living water poured out by God — His life and Spirit.
Full interpretation
Verifiable historical, etymological and topographical statements are accompanied by sources. The theological conclusions are the project’s interpretation according to its published methodology.
The Southern Fish is an extremely ancient image. In Mesopotamian texts long before the Greek myths there existed the constellation MUL.KU₆ — 'Fish', Akkadian nūnu. Researchers of ancient astronomy identify it precisely with the region of the Southern Fish and Fomalhaut. In MUL.APIN it is among the 'stars of Ea' — a deity associated in Mesopotamian tradition with fresh water; moreover, ancient depictions of Ea show fish next to streams of water flowing from him. This makes the combination of Fish + pouring water much older than the Greek story of Aquarius.[Hunger & Pingree · MUL.APIN][Rogers · Origins][Вавилонские звёздные каталоги][Stellarium · MUL.APIN][Kunitzsch & Smart][IAU · имена звёзд]
The sky map reveals the main meaning of the constellation even more clearly. Aquarius pours a long stream of water downward, and this stream ends not at the ordinary Fishes, but directly in the mouth of the Southern Fish. Even Ptolemy assigned Fomalhaut simultaneously to the Southern Fish and to the stream of Aquarius. The very name Fomalhaut comes from the Arabic Fam al-Hūt — 'mouth of the Fish'. Thus, one of the brightest stars in the sky marks precisely the place where the celestial water enters.[Kunitzsch & Smart][IAU · имена звёзд]
Therefore the Southern Fish is best understood not as a random copy of the ordinary Fishes, but as another aspect of the same people of God. The constellation Pisces shows two parts — Israel and the Church — joined by one knot and awaiting final deliverance. The Southern Fish shows the result of God's action upon them: the people are no longer divided into two figures, but presented as one Fish that lives by the water coming from above.
This fits especially well with the New Testament. Jesus spoke of two groups of sheep that in the end become 'one flock'. So too here: the two Fishes may convey the distinction between Israel and the Church in the history of salvation, while the one Southern Fish conveys the final unity of God's people, receiving the same life from God.[Kunitzsch & Smart][IAU · имена звёзд]
At the same time, the most ancient data unexpectedly confirm that the Southern Fish is even older than the image of the two Fishes in its familiar form. In the ancient Babylonian system, the region of modern Pisces was originally called not two fishes, but the 'Tails of the Swallow'; the fish image formed there later. And MUL.KU₆ — properly the 'Fish' of ancient Mesopotamia — refers precisely to the Southern Fish. Therefore, if one seeks the oldest original celestial image of God's people as a Fish, the Southern Fish proves especially important.[Hunger & Pingree · MUL.APIN][Rogers · Origins][Вавилонские звёздные каталоги][Stellarium · MUL.APIN][Kunitzsch & Smart][IAU · имена звёзд]
Thus, the sequence becomes very expressive: Aquarius — God pouring out living water; the stream — the Spirit and life coming from Him; the Southern Fish — the people of God receiving that life. The Fish does not produce the water itself — it opens its mouth and receives it from above. This is an image of a man and a people whose life depends entirely on what God pours out.