The Contention Between Samas and Merodach
“With the spread and fame of the empire of Sargon, the worship of Samas spread and became famous also. The empire and the cult were alike Semitic; wherever the Semite planted himself, the Sun-god was worshipped under some form and name.
The extent, therefore, of the worship of the Sun-god of Sippara marks the extent and power of Sargon’s kingdom. The older Samas of Larsa was eclipsed by the new deity; henceforward Sippara, and not Larsa, was the chief seat of the adoration of Samas in Babylonia. It is to Sippar in all probability that the hymns addressed to the Sun-god belong.

Bas relief of the Tablet of Shamash, portraying the god Shamash on his throne, IXth century BCE. British Museum.
They are the product of an age of new ideas and aspirations. They represent the meeting and amalgamation of Semitic and Accadian thought. The scribes and poets of Sargon’s court were partly Semites, partly Accadians; but the Semites had received an Accadian education, and the Accadians had learnt the language and imitated the style of their Semitic masters.
Though the originals of most of the hymns are written in the old language of Accad–a language that had become sacred to the Semites, and in which alone the gods allowed themselves to be addressed–the thoughts contained in them are for the most part Semitic.
We have no longer to do with a Mul-lil, a lord of ghosts and demons, nor even with an Ea, with his charms and sorceries for the removal of human ills, but with the supreme Baal of Semitic faith, the father and creator of the world, who was for his adorer at the moment of adoration the one omnipotent god.
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In the closing days of the Babylonian monarchy, Nabonidos, after restoring the temple of the Sun-god at Sippara, addresses him in the following words:
“O Samas, (mighty lord) of heaven and earth, light of the gods his fathers, offspring of Sin and Nin-gal, when thou enterest into E-Babbara, the temple of thy choice, when thou inhabitest thy everlasting shrine, look with joy upon me, Nabonidos, the king of Babylon, the prince who has fed thee, who has done good to thy heart, who has built thy dwelling-place supreme, and upon my prosperous labours; and daily at noon and sunset, in heaven and earth, grant me favourable omens, receive my prayers, and listen to my supplications. May I be lord of the firmly-established sceptre and sword, which thou hast given my hands to hold, for ever and ever!”
Nabonidos, the Babylonian, the peculiar protege of Merodach, could not regard Samas with the same eyes as the old poets of the city of the Sun-god. His supreme Baal was necessarily Merodach, whose original identity with Samas had long since been forgotten; and Samas of Sippara was consequently to him only the Baal of another and a subject state.
Samas is therefore but one of the younger gods, who illuminates his divine fathers in the higher heaven. He shares the power and glory of his fathers only as the son shares the authority of the father in the human family.
Nothing can illustrate more clearly the local character of Babylonian religion than this difference between the position assigned to Samas in the hymns and in the inscription of Nabonidos.
In the one, he is the supreme god who brooks no equal; in the other, the subordinate of Merodach and even of the Moon-god Sin.”
A.H. Sayce, Lectures on the Origin and Growth of Religion as Illustrated by the Religion of the Ancient Babylonians, 5th ed., London, 1898, pp. 170-5.