An invocation is a request for the spiritual presence and blessing of a deity during a rite. To invoke is to call upon earnestly, so an “invocation” in the context of prayer is a serious, intentional calling upon a God or Goddess. In Hellenic ritual, it's common for prayers of invocation to be offered every time a new deity is invoked, so we can be sure They will the hymns and prayers of petition offered to Them. Invocations fit into the rite like so:

- Lighting of the incense burner with frankincense
- Invocation to Demeter: Khaire Demeter, you who taught us to work the earth and provides for us so bountifully…
- Libation of a kykeon and sacrifices
- Orphic Hymn 40 To Eleusinian Demeter
- Prayers

A few days ago, I put up a list of invocations from the Iliad. People seemed to like it, so let's do another one today: from the Odysseia, because that is the logical step! The Odyssey (Ὀδύσσεια) is, in part, a sequel to the Iliad, the other work ascribed to Homeros. The Odyssey was composed near the end of the 8th century BC and focuses mainly on the hero Odysseus, king of Ithaca, and his journey home after the fall of Troy. It takes Odysseus ten years to reach Ithaca. In his absence, it is assumed Odysseus has died, and his wife Penelope and son Telemachus must deal with a group of unruly suitors, who compete for Penelope's hand in marriage. Needless to say, Odysseus keeps his lady love! There aren't as many invocation in this story as most of the characters tell their story themselves, but there are a few.

"Great Goddess Artemis, daughter of Zeus..."

"Hear me, daughter of Aegis-bearing Zeus, unweariable..."

"Rosy-fingered Eos, child of morning..."

"O thou that encirclest the earth, vouchsafe to grant the prayers of thy servants that call upon thee..."

"I pray you by Themis, who is the beginning and the end of councils..."

"Hear me, O King..."
"Father Zeus, and all you other gods who live in everlasting bliss..."
"Father Zeus, you who rule over heaven and earth, you have thundered from a clear sky without so much as a cloud in it, and this means something for somebody; grant the prayer, then, of me your poor servant who calls upon you..."