Historical origins of the doctrine of God's self glorification

Although I can clearly see its Biblical precedent, it seems to be a question that was not explicitly addressed until the Reformation.

This "doctrine of self glorification" can actually be found in the earliest Judaic writings:

"I have fashioned this nation for Myself, they will relate my praise" (Isaiah 43:21)

and

"You are my servant, O Israel, through whom I will be glorified" (Isaiah 49:3)

The majority of Biblical scholars believe that the written books of the Torah were a product of the Babylonian captivity (c. 6th century BCE), based on earlier written sources and oral traditions, and that it was completed with final revisions during the post-Exilic period (c. 5th century BCE). The Hebrew religion out of which Judaism evolved, was polytheistic, becoming officially monolatrous during the late monarchy and monotheistic around the time of the Babylonian Exile.

This means that many of the oldest Torah texts were first written or finalized during the transition from polytheism to monotheism. Many echoes of the "struggle for supremacy" between these (usually city) deities can be found in the OT.

According to the available evidence, Israelite religion in its earliest form did not contrast markedly with the religions of its Levantine neighbours in either number or configuration of deities (See Mark S. Smith: The Early History of God). At some stage Yahweh joined the Israelite pantheon, possibly from Midian, where Egyptian records show that a god called YHW was worshipped. "Self-glorification" as witnessed in the texts of the OT is an obvious way to make Yahweh the top deity.

Yahweh (YHWH) was worshipped during the early, polytheistic centuries of Israel and Judah, although it is thought that Yahweh only entered Hebrew belief some time after the people became established as identifiable groups. So, Yahweh clearly was a polytheistic deity. The Canaanite father of the gods was El (Hebrew: Elohim), but Yahweh became the national god and then syncretised with El as one supreme God above all others. Evidence of this syncretization is easily found in the OT:

(Exodus 6:7)

Many verses take on a completely different meaning if you know of the polytheistic origin of Judaism:

Thou shalt have no other gods before me (Exodus 20:3)

Thou shalt not bow down thyself to them, nor serve them: for I the Lord thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth generation of them that hate me; (Exodus 20:5)

Clearly these self-glorifying statements make more sense in a polytheistic context before Yahweh became the state deity.

One of the titles that Yahweh calls himself, "El Shaddai" (usually translated as the almighty) takes on a very different meaning in the aforementioned Midian origin of Yahweh:

The biblical account describes the Midianites as worshiping more than one deity, including both Baal-peor and Yahweh. Both of these deities are likewise described as being worshiped by the Israelites themselves, although Baal worship was supposedly forbidden to them. Scholars speculate that the worship of Yahweh may have actually begun among the Midianites and was later adapted by the Israelites. Supporting this theory is the fact that Exodus states that God was known as as El-Shaddai by the Israelites until Moses' encounter with Him at Sinai, after first meeting the Midianite priest Jethro and marrying into his family:

Moses’ father-in-law replied, “What you are doing is not good. 18 You and these people who come to you will only wear yourselves out. The work is too heavy for you; you cannot handle it alone. 19 Listen now to me and I will give you some advice, and may God be with you. You must be the people’s representative before God and bring their disputes to him. 20 Teach them his decrees and instructions, and show them the way they are to live and how they are to behave. (Exodus 18)

After this event we get Mozes' encounter, where Yahweh states:

(Exodus 6:3).

In conclusion, not only does self-glorification clearly predate the Reformation, but its origin is very likely strategical writing to ultimately establish an imported Yahweh as the state deity and to syncretize this deity with Elohim.

There is a good section on the Glory of God in the Catholic book I quote from below. First, examination is made of some of the Hebrew and Greek biblical texts that speak of God's glory. Then quotes are given from centuries before the Reformation, and as you specifically ask for such ancient quotes, I will give them. Note that the comments following (by writer of that article, Humbert Bouesse) show the correct understanding of what the Glory of God means, and it isn't what most people think it means.

"On Prov. 16:4, Aquinas says: 'The Lord made all things to communicate himself' (Summa Theologica, I, q. 44, a. 4). Irenaeus says, 'To those who see God, his glory gives life... participation in the life of God is the vision of God and the enjoyment of his blessings... the glory of God is the living man, the life of man is the vision of God.' (Adv. Haereses, IV, 19; PG, VII, cols. 1035-37).

a) Hence, the external glory of God means primarily the subjective attitude of adoring acknowledgment of the majesty of God. It is an act of adoration before the absolute mystery.

b) This act is directed to God's self-revelation, insofar as it manifests the majesty of God in its power and splendour. This self-revelation takes place in and through creation which through its being and through its response reveals God's glory and finds its purpose there. The unsurpassable eschatological revelation takes place in Christ Jesus, as the climax of the history of salvation.

c) The manifestation of the glory of God in history is again based on his fulness of being, his intrinsic power and majesty, as known and affirmed by God himself. This cannot be impaired, extrinsically or intrinsically, and hence constitutes his holiness." (Encyclopedia of Theology - a concise Sacramentum Mundi, edited by Karl Rhaner, 1981, p567)

"The phrases, 'the glory of God', 'give glory to God', 'act for the glory of God', are part of accepted Christian usage but they need to be properly explained. Understood in too anthropomorphic a way, they fail to do justice to the divine transcendence and hence to the absolutely free and disinterested love of God in his dealings with the world. (Ibid. p575)

Then the article goes into ancient Hebrew and koine Greek to show the biblical meaning of God's Glory, the Glory of the Son, and how the whole creation longs and groans for this glory (Rom. 8:19-23). It adds that:

"The glorification of God, of Christ and of men go together (2 Cor. 4:15) ...God created the world "not to increase his blessedness or to acquire it, but to manifest his perfection" (Vatican I, D 1783, 1803). (Ibid. p576)

I conclude by repeating the significant truth that all Christians can agree with, that God's Glory constitutes his holiness. God is love. God is light. God is righteous. God is so much more, but with regard to this answer, God is holy. Put all that God is together, and there you see the Glory of God, even though that can also be seen in each of his divine qualities. God does not have to glorify himself. He IS glorious. Sentient beings have the duty to declare God's Glory, and that brings joy unspeakable. I would also add that the doctrine was explicitly and exquisitely addressed by the Reformers far more-so than at any previous time.