Category:
1 Introduction
mathematical taxonomies
2 Hesiod and the Scholia
Hesiod, at the end of his Works and Days, gives a hemerology or lunary (account of the days of the lunar month) of some length. In its course, he mentions some sacred days, specifically saying that Leto bore Apollon on the seventh (which is why it is sacred), while the fifth is terrible, because on it, Eris gave birth to Horkos (Oath), with the Erinyes as midwives.
In the ancient Scholia (explanatory comments), the Hesiodic hemerology is augmented with material from Philochorus, an Atthidographer or writer on Athenian antiquities. However, the scholiasts do not mark the information from Philochorus as peculiarly Attic, but treat it as relevant to the interpretation of the Boeotian poet Hesiod, reflecting a degree of interpermeation of the two strands in mainstream Greek culture.
In the future, I hope to translate the Hesiodic hemerology, with the ancient scholia, in full; on this page, I will confine myself to the associations of days with gods, derived primarily from the Scholia.
Summary list
(1) “Philochorus, in On the Days, says it belongs to the Sun and Apollon” (Scholia on 770).
(3) “Philochorus says that all thirds” – 3rd, 13th and 28th (or 23th; but the days of the last third are often counted backwards) – “are sacred to Athena” (Scholia on 780).
(4) “The fourth belongs to Heracles and Hermes […] the fourth is sacred to Heracles because he was born on it” (Scholia on 770). “The fourth is sacred to Aphrodite and Hermes” (Scholia on 800).
(5) “All fifths”, that is to say, the 5th, 15th and 26th (or 25th; but the days of the last third are often counted backwards) are to be avoided as belonging to Horkos (Scholia on 802).
(6) The sixth “is sacred to Artemis, as the birthday of the goddess” (Scholia on 785).
(7) “The seventh is sacred to Apollon, for he was born on it, and for that reason his lyre is seven-stringed” (Scholia on 770).
(8) “They say that the eighth of the month is sacred to Poseidon” (Scholia on 790).
(13) Athena; see on the 3rd.
(15) Horkos; see on the 5th.
(23/28) Athena; see on the 3rd.
(25/26) Horkos; see on the 5th.
3 Vergil and Scholia about the 5th
…
Vergil
…
Servius
…
4 Attic and general Greek custom
[… parallels outside Athens]

Synthetic list
(1 = Noumenia) Apollon
(3) Athena
(4) Heracles, Hermes and Aphrodite;
also Hermaphroditus (Theophrastus, On Superstition)
(6) Artemis
(7) Apollon
(8) Poseidon
and Theseus (specific to Athens)
(13) Athena
(16) Artemis (perhaps also 25th, the “sixth day of the waning month”)
(28) Athena (28th = “third day of the waning month”)
(30) Hekate and the dead
Some commonly repeated, but tenuous or dubious associations
(1) Although there is evidence (both from Athens and elsewhere) for the worship of some other gods on the Noumenia, I cannot find any indication that the day was formally regarded as sacred to any specific god other than Apollon. (And often not even Apollon was specified.)
(2) The second is sacred to Agathos Daemon (see there), but it is not absolutely certain that this was observed in Athens.
(4) There is only indirect and rather thin evidence for the fourth being observed as sacred to Eros: firstly, Plato, Symposium 203c says that his birthday is the same as Aphrodite’s; secondly, there is a record of one private celebration of Eros on the 4th of Mounichion.
(8) The eighth is not generally sacred to Asclepius; it only featured a sacrifice to him in the month of Elaphebolion (Aeschines 3.67).
(9) I have not been able to find out why pagan books and websites associate the ninth with the Sun (Helios) and Rhea. (Any information about this from readers would be appreciated!) Their connecting the ninth to the nine Muses and their mother Mnemosyne has a more obvious basis, but to my knowledge there still no ancient evidence of the ninth day in particular (rather than the number nine in general) being sacred to the Muses.
[Apollon Noumenios/Neomenios; Philochorus]
Scholia on Aristophanes, Plutus 1126
“The fourth used to be observed for Hermes; and in each month, the same day would be dedicated to Hermes. In addition to the festivals, certain days of the month were held as sacred to certain gods by the Athenians, like the Noumenia (the first) and the seventh to Apollon, the fourth to Hermes, and the eighth to Theseus; the third to the Graces.”
Another scholium: “The Noumenia and the seventh were consecrated to Apollon; the fourth to Hermes; the sixth to Artemis; and so on.”
[Hêrakl-. Tetradi gegonas. Artemis: Plutarch, Alexander 3.5. Plutarch: Thês- ogdo-; Poseid- ogdo-; scholia on Hesiod. ‚Tais ogodais ta Qhseia‘]
Hesychius, s.v. ὀγδοαῖον
“The octonary (ogdoaîon) is a sacrifice consecrated by the Athenians to Theseus.”
[16th Artemis. 28th Athena. Hekate triaka-. Mikalson PDF p. 29ffff]
5 Traditions that may not be related to Athens
[Agathos Daemon on the 2nd. Pan on the 10th]
Etymologicum Magnum, s.v. Εἰκάδιος
“Eikadios: From eikás eikádos, ‘twentieth’, eikádios, ‘he of the twentieth’. It is a proper name. On the twentieth of the month, a holiday would be celebrated for Apollon; and it used to be called the twentieth-sacrifice (hiéreia eikás). Now, (Apollon) is called Eikadios because he was born on this holiday.”
6 From Lunaries
Lunaries or selenodromies are lay astrological texts about the nature or meaning of the thirty days of the month. I hope to translate these fully in the future, gods willing, but for now present only the birthdays of the gods which they list.
Information taken from the lunary in CCAG (Catalogus Codicum Astrologicorum Graecorum) XI.1, p. 134–144:
(1) Hermes was born.
(2) Phosphoros (planet Venus) was born.
(3) Wind was born.
(4) Ares was born.
From the lunary in CCAG XI.1, p. 121–122:
[I currently have no access to this version.]
From the lunary in CCAG XI.1, p. 196–200:
(21) Abrasax (MS Abradáx) was born.
(29) Athena was born.
From the lunary in CCAG III, pp. 32–40:
(1) —
(2) Phosphoros was born.
(3) Winds (ánemoi) and breaths (thymoí) were born.
(4) —
(5) Interpretation (hermēneía) was born.
(6) Artemis was born.
(7) Apollon was born.
(8) Poseidon was born.
(9) Grace (kháris) was born.
(10) Wealth (ploûtos) was born.
(11) Memory (mnēmosýnē) was born of Kronos and Rhea.
(12) Justice (dikaiosýnē) was born.
(13) Dionysus was born.
(14) Hope (elpís) and Thought (énnoia) were born.
(15) Hephaestus was born.
(16) Dioscorus was born.
(17) Sleep (hýpnos) and Death (thánatos) were born.
(18) Truth (alḗtheia) was born.
(19) Muse(?) (MS Mōsês) was born.
(20) Demeter was born.
(21) Kronos(?) (MS Krianós) was born.
(22) Victory (níkē) was born.
(23) Leto was born.
(24) Ares was born.
(25) Pride (hyperēpháneia) was born.
(26) Nymph was born.
(27) Zeus was born.
(28) Day (hēméra) was born.
(29) —
(30) Wealth (ploûtos) and Fortune (týkhē) were born.