Without covering ground already exegeted over the last decade in numerous threads here, the "banner," defined as a priestly ornament, is fundamentally related to three idolatrous icons found in the scripture. The first is Moses' rod, later named Nehushtan, which is itself directly associated with the breastplate of the high priest, called the "chosen," and finally, the bosom-borne rod of judgement, the branch bearing the fruit of salvation, aka, the crucifix:
FOR I LIFT UP MY HAND TO HEAVEN. By way of the plain meaning of Scripture this is an oath by His throne. He states I lift up, for whoever takes an oath raises his hand and touches the object by which he swears. And by way of the Truth [the mystic teachings of the Cabala], during the time of exile He hath cast down from heaven unto the earth the beauty of Israel. He, therefore states that now in an acceptable time He will lift His hand to the highest heavens, the reference being to the great hand that fights on behalf of Israel.
Ramban, Commentary on the Torah, Deuteronomy 32:40 (emphasis mine).
Thus saith the Lord God, Behold, I will lift up mine hand to the Gentiles, And set up my banner to the People [of Israel]. And thy sons shall enter [Zion] with it in their bosom, and thy daughters shall wear it around their neck [over their shoulders].
Isaiah 49:22.
For he [God] hath clothed me with garments of salvation, covered my bosom with righteousness, as the ornament [חשן] of a circumcised priest, which is like the jewelry a bride wears between her breast.
Isaiah 61:10.
The genesis of the three idolatrous icons occurs when Moses meets the Lord hidden behind the burning bush on the mount of God. At that time the Lord God informs Moses that he (Moses) has been chosen to lead the People of Israel to the promised land. When Moses replies that only if they believe he's seen the Lord God himself would the People trust him, God responds in the most ironic fashion: What's that in your hand. God subsequently informs Moses that his serpent rod, later called Nehushtan, is an idolatrous icon representing the burning bush, and thus the theophany of God that Moses personally experienced.
The three quotations of scripture given above segue to Moses on the mount, with God in the burning bush. After informing Moses that Nehushtan, his serpent rod, is an ornament, or banner, representing the burning bush, he, the Lord, then tells Moses something that should make anyone following this exegesis snap to attention: Place the burning bush, the theophany of the Lord, in your bosom, where it will become as leprous as snow; and then pluck it out of thy bosom where it will be healed and as other flesh.
God next informs Moses of something seminal to Isaiah's prophesy. He tells Moses that if Israel doesn't believe the theophany associated with the leprous, bosom-borne icon of the burning bush, i.e, the leprous theophany of the Lord, then when it's plucked out of God's bosom and made normal flesh again, that is, redeemed, saved, from the leprosy, then, if not before, Israel will believe (Exodus 4:6-7).
Why withdrawest thou thy hand, even thy right hand? Pluck it out of thy bosom.
Psalms 74:11.
Then his people recalled the days of old, the days of Moses and his people --- where is he who brought them through the sea with the shepherd [rod] of his flock? Where is he who set his Holy Spirit among them, who sent his glorious arm of power [Nehushtan] to be at Moses' right hand, who divided the waters before them, to gain for himself everlasting renown . . . you are our Father, though Abraham doesn't know us or Israel acknowledge us; you, O Lord, are our Father, our Redeemer from of old is your name.
Isaiah 63:11-16.
John