«Nam quid divinius isto ut puncto exiguo culpa cadat populi?»

«In fontibus qui beati Iohannis ascribuntur, Deo opitulante a beato Ambrosio, cunctis fidelibus adstantibus et videntibus, in nomine sanctae et individuae Trinitatis (Augustinus) baptizatus et confirmatus» («In the baptismal font named after Saint John, with the help of God and in the presence and in the sight of all the believers, by Saint Ambrose Augustine was baptized and confirmed in the name of the holy and undivided Trinity»). It was, therefore in the baptistery of San Giovanni alle Fonti, according to the tradition handed on by Landolf the Elder at the beginning of the 12th century, in the Historia mediolanensis (I, 9), that Augustine received baptism in Milan from Ambrose at the Easter vigil between the 24th and 25th of April, 387.
For the building of this baptistery, whose archaeological remains, adjacent to those of the ancient basilica dedicated to the virgin and martyr Saint Tecla, lie about four meters under the parvis in front of the Cathedral (one gets there from inside the cathedral), Ambrose himself composed a hymn of eight lines in two stanzas, that, perhaps set up on the inside walls of the building, were meant to be read in relation to the eight sides of the baptismal font. As with, for example, the verses composed by Pope Sixtus III (432-440) to be found in the baptistery of Saint John Lateran in Rome (also known, from its origins, by the name of “San Giovanni in Fonte”), there, however, on the architraves that link the eight pillars set around the font.
Among the various buildings that tradition attributes to Ambrose, the baptistery is sure, thanks to the excavation conducted in the autumn of 1996 (after the first excavations of 1961-62) that brought to light items of certain date: a coin of Valentinian, emperor from 364 to 378 A.D., found in one of the passages in front of the building; carbon dating of fragments present in the mortar used in one of the outside corner panels; the dating to 387 A.D. +/- 145 by thermoluminescence of a brick used in the same panel (cf. S. Lusuardi Siena, M. Sannazaro, I battisteri del complesso episcopale milanese alla luce delle recenti indagini archeologiche, in L’edificio battesimale in Italia. Aspetti e problemi. Atti dell’VIII Congresso nazionale di Archeologia cristiana, 21-26 settembre 1998, Bordighera 2001, pp. 647-674).
The epigraphic composition by Ambrose, certainly transcribed in the 8th century and passed on then by the manuscript tradition in the Palatino Latin Codex 833 (fol. 41r-v) by an unknown author of the 9th or early 10th century, kept in the Vatican Library, must also date to the years immediately before 387, perhaps to 386. The text, given in various epigraphical collections of the 19th and 20th century (De Rossi, Bücheler, Corpus Inscriptionum Latinarum, Diehl), was most recently republished in Opera omnia di sant’Ambrogio. Inni, Iscrizioni, Frammenti, edited by S. Banterle, G. Biffi, I. Biffi, L. Migliavacca, Milan 1994, pp. 96-99, with some slight variation from the text of the codex that is given on the previous page (with the sole correction of an obvious copyist’s error).
Though not all scholars agree on the authenticity of some of the various epigraphical texts attributed to Ambrose, this particular composition provokes no doubts, both on the basis of comparison with writings unquestionably by Ambrose (cf. O. Perler, L’inscription du baptistère de Sainte-Thècle à Milan et le “De sacramentis” de saint Ambroise, in Rivista di Archeologia Cristiana, XXVII 1951, pp. 145-166), and even more of the archeological correspondence with what remains of the ancient baptistery.
In its construction Ambrose went back to a secular and imperial design, known in Milan from the imperial mausoleum of San Vittore al Corpo: a building with an octagonal perimeter; a building type that was to be repeated later in the city in Sant’Aquilino, the shrine annexed to San Lorenzo and still intact in its original form. But Ambrose explicitly reinterpreted the architectural form symbolically: the number of sides of the baptismal font and of the building that contains it is not casual but deliberate, as is explicitly avowed in the verses themselves. So also the dedicatory epigraphical composition hingeing in its structure on the number eight (there are in fact eight distiches, that is couplets composed of hexameter and pentameter).
To understand the insistence on this number (and explain the reason for the diffusion of the octagonal baptistery type, of which one of the first was precisely that of San Giovanni alle Fonti, and the first probably that of San Giovanni in Fonte at the Lateran), one has to realize that the number eight, in the symbology of the early Fathers of the Church, indicates the day of the Lord, the dies dominica, following on the seventh, that is Saturday. While the number seven refers to Genesis (the days of the creation) and closes the Old Testament, symbolizing the law, the eight refers to the New Testament, to the accomplishing and going beyond of the old law, to the new creation, that is to the coming of Jesus, to the regeneration through baptism that frees from sin, to Jesus Christ risen from the dead, salvation for all men.
This simple and, for the early Christians, usual symbolic idiom, defended by Irenaeus of Lyons against the abstract constructions of the Gnostics (of Valentine and his followers in particular), is several times clearly referred to elsewhere by Ambrose himself when, for example, he says: «Septimus dies legis mysterium signat, octavus resurrectionis» (Epistola 26, 8: «The seventh day indicated the mystery of the law, the eighth that of the resurrection»), or, more amply: «Hebdomas veteris Testamenti est, octava novi, quando Christus resurrexit, et dies omnibus novae salutis illuxit. Ille dies, de quo ait propheta: “Hic dies, quem fecit Dominus, exsultemus et laetemur in eo” (Ps 117, 24); de quo die se fulgor plenae et perfectae circumcisionis humanis peccatoribus infudit. Propterea et vetus Testamentum dedit partem octavae in circumcisionis solemnitate. Sed illa adhuc in umbra latebat: venit sol iustitiae (Mal 4, 2) et consummatione passionis propriae revelavit sui luminis radios: quos retexit omnibus, et vitae claritatem aperuit aeternae» (Epistola 44, 4: «The seventh day is of the Old Testament, the eighth of the New, for Christ is risen, and the day of a new salvation for all has appeared bright. That day, of which the prophet says: “This is the day made by the Lord: let us be glad and exult in it”; since that day the splendour of full and perfect circumcision has come in among sinful men. Hence the Old Testament has participated in the eighth day with the solemnity of circumcision. But that still remained hidden in shadow: the sun of justice has come and in the fulfilment of his own passion has revealed the rays of his light: and he has revealed them to all, and has made visible the splendor of eternal life»).
Even the very structure of the place, then, was designed to make visible, to make clear to the eyes and minds of believers the new life in Christ, to which one accedes through the sacrament of baptism.



Versus Ambrosii ad fontem eiusdem ecclesiae [sanctae Tecle]

OCTACHORVM SANCTOS TEMPLVM SVRREXIT IN VSVS
OCTAGONVS FONS EST MVNERE DIGNVS EO
HOC NVMERO DECVIT SACRI BAPTISMATIS AVLAM
SVRGERE QVO POPVLIS VERA SALVS REDIIT
LVCE RESVRGENTIS CHRISTI QVI CLAVSTRA RESOLVIT
MORTIS ET E TVMVLIS SVSCITAT EXANIMES
CONFESSOSQVE REOS MACVLOSO CRIMINE SOLVENS
FONTIS PVRIFLVI DILVIT INRIGVO
HIC QVICVMQVE VOLVNT PROBROSA[E] CRIMINA VITAE
PONERE CORDA LAVENT PECTORA MVNDA GERANT
HVC VENIANT ALACRES QVAMVIS TENEBROSVS ADIRE
AVDEAT ABSCEDET CANDIDIOR NIVIBVS
HVC SANCTI PROPERENT NON EXPERS VLLVS AQVARVM
SANCTVS IN HIS REGNVM EST CONSILIVMQVE DEI
GLORIA IVSTITIAE NAM QVID DIVINIVS ISTO
VT PVNCTO EXIGVO CVLPA CADAT POPVLI





Verses by Ambrose by the font of this same church [Santa Tecla]:

The temple of eight niches rises for sacred uses,
the octagonal font is worthy of this gift.
It was right that on this number the hall of sacred baptism
should rise whereby true salvation has been given back to people
in the light of Christ resurgent, he who opens the prison
of death and wakes the lifeless from the tomb,
and, freeing from the stain of sin those who confess their guilt,
washes them in the current of the pure-flowing font.
Here all those who want to abandon the guilts of a vile life
Let them wash their hearts, safeguard a clean mind.
Let them come prompt here: and though benighted, who approach
do dare, will leave whiter than the snow.
Here hasten the saints: of these waters ignorant
there is no saint, in them is the kingdom and design of God.
O glory of justice! For what is more divine than this
that in a brief instant the guilt of a people crumble?

(translation in English from the Italian traslation by Lorenzo Bianchi)