Commenting on Isa 6 and Isaiah’s prophetic call, Bernhard Anderson (1916-2007), at the time of writing, the professor of Old Testament Theology at Princeton Theological Seminary, wrote:
Yahweh’s speech employs the plural “us” (Is. 6:8), for he is surrounded by his Council, his heavenly host, to whom and for whom he speaks. Isaiah, then, is drawn into Yahweh’s Heavenly Council where the divine decrees are announced and where messengers are sent forth to execute them. (Bernhard W. Anderson, The Living World of the Old Testament [3d ed.; Essex: Longman Group Limited, 1975], 304, emphasis added)
Commenting on the theology of the Heavenly Council in the book of Isaiah, Anderson elsewhere wrote:
In the Heavenly Council
The setting of the opening poem (40:1-11) I placed in heaven, where Yahweh’s Council is assembled. Several times before, we have noticed that prophetic authority rested upon a direct commission given to the prophet standing in this Council (see Jer. 23:18), as, for instance, in the case of Isaiah’s vision in the Temple. So the prophecy of Second Isaiah begins with good news heard in the Heavenly Council. Then the poetry moves from heaven to earth. Since the first poem serves as a prologue to the whole poetic cycle, we shall give it special attention.
In the ancient view, the decisions affecting human destiny were made in the Heavenly Council. According to the Babylonian creation myth, Enuma elish which was recited in the temple of Babylon during the New Year’s Festival, the council of the gods invested Marduk with supreme authority and acclaimed him in the shout: “Marduk has become king!” His victory over the monster Tiamat and her allies gave assurance that for the coming year the world would be subject to the high god’s sovereign decrees. Perhaps Second Isaiah, who must have been familiar with Babylonian myth and ritual, was influenced by this religious background as he portrayed Yahweh’s kingship over the world. His deepest debt, however, was to the prophets who preceded him, and to the great convictions that were celebrated in Israel’s worship in the context of the “Zion theology.” He was heavily dependent upon the hymns and liturgy of the pre-exilic worship services of the Jerusalem Temple, especially the services of the Fall festival when a number of psalms (47, 93, 96-99) were used to extol Yahweh as King of the nations and of the whole universe. So Second Isaiah was speaking primarily out of Israel’s tradition in his portrayal of Yahweh, the King par excellence. Thus his first poem begins with two imperatives, “comfort, comfort.” In the Hebrew text these imperatives are in the plural, because God is speaking to his heavenly servants, announcing the destiny of Israel and the nations. (Ibid., 446, emphasis added)
Finally, commenting on Isaiah’s critiques of idolatry, we read:
Fundamentally, his critique of the idols is that they are powerless in history, and therefore they are nothing. Again and again he challenges the nations to bring proof that their gods have been able to announce a plan in history and carry it through (42:5-17; 43:8-13; 44:6-8, 21-23; 44:24-45:13; 48). With some caricature of Babylonian worship, he pokes fun at the idol-making industry (see 40:18-20; 44:9-20), arguing that these artifacts are mere expressions of human cleverness and power. Man-made idols do not have the divine power to control the issues of history, nor can they sustain the meaning of life from birth to old age. With fine satire, he ridicules the Babylonian idols, Bel and Nebo—the very gods whom, according to the Cyrus Cylinder, Cyrus restored to their sacred cities—who have to be loaded on the backs of dumb animals, causing them to strain and stoop under the burden. These pathetic gods have to be carried, but—says the prophet—Yahweh carries his people and lifts their burdens. He alone has the power to save and to accomplish his purpose in history. (Ibid., 455)