FISH. — It is one of the oldest Christian symbols. In Greek, fish is called IXOYC, and the letters that compose it form the acrostic IHCQYC XPICTOC OEOY YIOC CNTIIP, that is, Jesus Christ, Son of God, Saviour (Optatus, De schismate Donatistarum, 3, 2: CSEL, 24, p. 68). St Augustine warns that the roasted fish is a symbol of Christ’s Passion (In Johann. Tract., 123: PL 35, 1966). There are many Christian inscriptions with the symbol of the fish; G. B. De Rossi collected a group of them as early as 1855 (Epistola de christianis monumentis IXOYN exhibentibus, in Spicilegium Solesmense, 3 [1855], pp. 573 ff.).
The texts relating to the symbol of the fish were collected in a study by H. Achelis (Das Symbol des Fisches und die Fischdenkmäler der römischen Katakomben, Marburg 1888); but the most important work on the subject, both for the literary sources and for the analysis of the monuments, was carried out by F. J. Dölger (IXOYC Das Fischsymbol in frühchristlicher Zeit, I, Münster 1928; II and III, ibid. 1922; IV, ibid. 1927; V, ibid. 1932-40).
Abercius recalls the fish as a great and pure fountain from which the chaste virgin takes and offers to eat to her friends every day. In the first part of the poem inserted in the inscription of Pettorius, besides the acrostic IXOYC, we find: divine race of the heavenly IXOYC which is eaten eagerly; and Pettorius commends himself to all his loved ones who are in the peace of the IXOYC. The word was scratched into the plaster of a mausoleum discovered beneath the basilica of St Sebastian on the
Appian Way, with the letter T (sign of the Cross) also added (G. Mancini, Scavi sotto la basilica di S. Sebastiano sull’Appia Antica, in Notizie degli Scavi, 1923, pp. 3-79). An inscription from the Vatican reads: IXOYC ZUNTOUN, that is, fish of the living, who gives life (G. Marchi, Monumenti delle parti primitive, Rome 1844, p. 70). The same word also appears in the inscriptions of Postumius Eutherion (Dölger, op. cit., I, fig. 11), of Eutychianus (loc. cit., I, fig. 13), of Colonus (loc. cit., pl. I, no. 103), of Caecilia Placidina (O. Marucchi, Monumenti del Museo cristiano Pio-Lateranense, Milan 1910, pl. 51, 13), of Modena where the fish is also depicted and the word fish is written in full (G. B. De Rossi, Roma sotterranea, II, Rome 1867, p. 333); of Callistus, etc. (found in Priscilla, in Domitilla, in Praetextatus, in Pamphilus; G. Wilpert, La Croce nelle catacombe, in N. Bull. arch. crist., 8 [1902], p. 10 and pl. 6, 3).
Tertullian states that we Christians are little fish, we are born in the water, according to our great fish Jesus Christ, and we are saved only by remaining in the water (i.e., in the grace of Baptism). This explains the frequency of early Christian epitaphs with fish facing loaves and even more facing the anchor; with the anchor and the Good Shepherd in the inscription on the sarcophagus of Livia Primitiva (G. Wilpert, Principienfragen der christ. Archäologie, Freiburg in Br. 1886, pl. 1, 1). A Greek inscription in the cemetery of Priscilla, placed by Claudius Philotas for his sweetest brother Theodore, ends with the wish that we may live in God, and then a fish is depicted, that is, in Jesus Christ, Son of God, Saviour (G. B. De Rossi in Bull. Arch. crist., 5th ser., 3 [1892], p. 14). In the cemetery of Callistus, in a cubicle from the end of the 2nd century, two fish are painted, with two baskets containing loaves and a cup with wine in front of them (Wilpert, Pitture, pp. 265-66 and pl. 27, 1 and 28). In the same cemetery, in cubicles A3 and A, bread and fish are depicted on a table (loc. cit., pl. 41, 1). In A2 and A3, bread and fish are depicted on a table (loc. cit., pp. 267-68 and pl. 38 and 41, 1). The feeding of the multitudes by the Sea of Tiberias (John 21:1 ff.) with loaves and fish is also in the same cubicle, where two plates with two fish are placed before seven men (loc. cit., p. 267 and pl. 41, 3); likewise in cubicle A2 (loc. cit., pp. 267-68, pl. 27, 2); and in cubicles A3 and A6 (loc. cit., pp. 268-69, pl. 41, 4 and 15, 2). Clement of Alexandria recommends that the faithful have the allegorical figure of the fish engraved on their rings (Paedagog., 3, 11).