Clytaemestra recognizes that the snake that she nursed in her nightmares was Orestes. Pylades and Orestes drag her into the house. The Chorus promises that Orestes, if successful, will give many offerings to Zeus. Orestes himself made a similar promise earlier. The promise of rich offerings to the gods occurs repeatedly in The Libation Bearers , but it is almost non-existent in other Greek tragedies.
Sacrifices are common, but in other plays offerings are frequently part of a complicated situation.
In Iphigeneia in Aulis and Iphigeneia in Tauris , sacrifice becomes complicated because the intended victim is human. In Antigone , sacrifice becomes impossible when the gods reject Thebes' offerings to show their disapproval of Creon. The sacrifice of animals was an ancient and conventional form of devotion in Greek religion. In the trilogy, the great method for this kind of explanation is the creation of teleology, a story that explains events in terms of an ultimate purpose or design. In the Oresteia , at least, this theme is present, as the whole bloody history of the House of Atreus ultimately leads to reconciliation of old gods with new and the creation of a new institution of justice.