Picture of the Sumerian god En-Lil (Akkadian/Babylonian: El-Lil)

Walter Reinhold Warttig Mattfeld y de la Torre, M.A. Ed.

Below a picture or photograph of a votive tablet showing two naked men presenting a drink-offering to two gods.
 
Professor Hilprecht (1903) identified the two naked men as being in reality _one_ individual, Ur-Enlil offering to his god Enlil a libation. If Hilprecht is correct, this is the only known representation of the Sumerian god Enlil that I am aware of.

Hilprecht's description follows:

"Votive Tablet of Ur-Enlil. About 4000 B.C. Upper section: Ur-Enlil offering a libation to Enlil (Bel).
Lower Section: A pastoral scene (goat, sheep, herdsmen)."

(cf. p. 417. Herman V. Hilprecht. Explorations in Bible Lands During the 19th Century. Philadelphia. A. J. Holman & Company. 1903)

I understand that this tablet recalls to the viewer's mind why the gods created man. One of man's duties was to feed the gods and care for their gardens in the edin and raise in this edin herds of animals to provide meat for the gods to dine upon. Man is also to provide water for the god's gardens surrounded by the edin via irrigation canals. So the cultic act of pouring not only recalls man providing drinks for the gods but also water for the gods' fields enabling produce for the gods' table (dates, figs, pomegranates, etc.). That is to say other scenes show a naked man pouring water upon a date-palm seedling with two date clusters, in a vase before a seated god, showing that man's duty is to provide irrigation water for the gods' gardens in the edin.