Laudator Temporis Acti

Jörg Rüpke, Religion of the Romans, tr. Richard Gordon (Cambridge: Polity, 2007), p. 73:

How would you recognize a god if you met one in the street? By the features I just mentioned: size, beauty, attributes; or by the divine scent that drifts about him (important in antiquity, a world without deodorants); or by his strangely radiant face.

By "attributes" Rüpke means (p. 75) "signs (objects) that regularly accompanied the image of a deity: at Rome, say, Jupiter's thunderbolt or his eagle, Minerva's owl, the helmet of Mars or Roma, the cornucopiae of Annona or a Genius."

On size, beauty, and attributes in epiphanies see the fake epiphany described by Herodotus 1.60.4-5 (tr. A.D. Godley):

There was in the Paeanian deme a woman called Phya, three fingers short of four cubits in stature, and for the rest fair to look upon. This woman they equipped in full armour, and put her in a chariot, giving her all such appurtenances as would make the seemliest show, and when they came into the town made proclamation as they were charged, bidding the Athenians "to give a hearty welcome to Pisistratus, whom Athene herself honoured beyond all men and was bringing back to her own citadel." So the heralds went about and spoke thus: immediately it was reported in the demes that Athene was bringing Pisistratus back, and the townfolk, persuaded that the woman was indeed the goddess, worshipped this creature and welcomed Pisistratus.

On sweet odors in epiphanies see Euripides, Hippolytus 1391-1393 (tr. David Kovacs):

O breath of divine fragrance! Though I am in misfortune I feel your presence and my body's pain is lightened. The goddess Artemis is in this place!

ὦ θεῖον ὀσμῆς πνεῦμα· καὶ γὰρ ἐν κακοῖς
ὢν ᾐσθόμην σου κἀνεκουφίσθην δέμας·
ἔστ' ἐν τόποισι τοισίδ' Ἄρτεμις θεά.

and Vergil, Aeneid 1.403-404 (of Venus, tr. H. Rushton Fairclough):

From her head her ambrosial tresses breathed celestial fragrance.

ambrosiaeque comae divinum vertice odorem
spiravere.

and Ovid, Fasti 5.376 (of the goddess Flora, tr. James George Frazer):

A fragrance lingered; you could know a goddess had been there.

mansit odor: posses scire fuisse deam.