I sat spellbound as a rabbi taught that the clean animals Isaiah mentions allude to God’s people Israel and the unclean to Gentiles. This gave new meaning to the ox and the ass and the millennial idea of harmony between the lamb and the lion. Although I don’t recall much of what the rabbi taught, he planted a seed that bore good fruit. Later, I discovered a network of synonymous parallel lines in the Book of Isaiah that figuratively depict one thing to mean another. A single verse could have multiple meanings: trees could represent people, forests represent cities, mountains represent nations, and so forth. Key end-time persons, I found, personified God’s attributes, such as righteousness and light, on the one hand, and anger and wrath, on the other.
But why would Isaiah resort to such indirect ways of speaking? First, when prophesying the end-time Isaiah confines himself to using precedents from the past as types. Where no such types exist, therefore, he must find other ways to say what he wants. Second, Isaiah doesn’t spell out everything. Only persons who deeply search his words and believe them will get his meaning. Third, his often seemingly incoherent writings protect them and those who understand them from prejudiced casual readers. Still, the method Isaiah uses limits him. Where will he find types from the past for what occurs in the end-time in instances where nothing like it happened before? Isaiah overcomes that obstacle by turning to metaphors—terms that function as pseudonyms or aliases.
Isaiah knows that God’s people have never before returned out of bondage from the four parts of the earth. Nor have they overthrown a world superpower like Assyria. Isaiah can prophesy those very things, however, within the context of Israel’s past. He has seen, for example, that events before Jehovah’s coming will involve two principal human actors: (1) a tyrannical king of Assyria—a destroyer; and (2) God’s servant and son—a deliverer. Whenever necessary, therefore, Isaiah can refer to these persons by means of aliases. Terms such as ensign, hand, rod, staff, mouth, voice, fire, and sword designate either individual, depending on the context. Each personifies those things. Terms such as light and darkness, on the other hand, set these two opponents apart.
Ancient Near Eastern mythology provides an additional source that Isaiah draws on. In the Ugaritic myth of Baal and Anath, for example, the terms Sea and River describe a god of chaos, an enemy whom Baal must conquer. These terms, therefore, suit Isaiah’s purpose as aliases of the king of Assyria. God’s raising his staff over the Sea and his hand over the River, for example, signifies a victory by God’s end-time servant and son (his staff and hand) over the king of Assyria (Sea and River). Personifying God’s anger and wrath, this evil ruler acts as a rod and staff to punish the wicked. In the end, however, God’s servant and son—his righteous rod and staff—breaks him. The key to these identities appears in the paralleled lines that establish these terms’ dual meanings.
(Taken from Isaiah Made Simple, pp 59–60)