You are asking about Revelation 5:12. I think your point is valid that understanding this passage can help us approach other parts of this and other apocalyptic writings. To approach it appropriately, I think we have to begin with verse 11 and continue through verse 13:
"Then I looked, and I heard the voice of many angels surrounding the throne and the living creatures and the elders; they numbered myriads of myriads and thousands of thousands, singing with full voice, 'Worthy is the Lamb that was slaughtered to receive power and wealth and wisdom and might and honor and glory and blessing!' Then I heard every creature in heaven and on earth and under the earth and in the sea, and all that is in them, singing, 'To the one seated on the throne and to the Lamb be blessing and honor and glory and might forever and ever!'" (NRSV)
This brief, vivid paragraph offers a very clear depiction of the nature of the universe. The “myriads of myriads and thousands of thousands” of angels inhabit a spiritual realm. It is the realm from which we enter into our human experiences, and the realm to which we return when each mortal life is concluded. Like the Christ Presence in each of us, the angels are expressions of divine creative energy. They are the Allness of God in spiritual expression, just as we are the Allness of God in both spiritual and human expression.
These angels—these myriads of beings who are our "siblings in spirit," like us in every way except that they have not entered into the human experience of limitation and duality (at least not at present)—are completely engaged in the joyful process of being expressions of the ineffable Divine. And part of their joy lies in supporting those of us—spiritual beings like them—who have undertaken the great creative process inherent in working through human limitations.
They are with us always, these angels. They love and appreciate the work we have undertaken in moving through illusions and challenges. They support us, they protect us, they remind us of the truth when we seem destined to forget it. They respect us too much to interfere with our process, but they encourage us to keep going. And they joyfully celebrate every hard-won step we take forward in consciousness.
That’s why they sing in praise of the great step forward represented by Jesus, whose life and ministry demonstrated the creative power of the Christ in each of us and the illusory nature of the limitations and negative energies that we allow to distract us. Indeed, all of creation joins in singing “to the one seated on the throne and to the Lamb”—to the Source of infinite love and to the expression of infinite love through the challenges of the human experience.
This is a universe of infinite love, joy and celebration. It cannot be threatened in any way by the illusions of negativity and conflict that we encounter in this human experience. It is a universe that always knows and affirms the spiritual Truth and that loves and guides us through challenges to fuller and fuller expressions of that Truth in our human lives. It’s important to see this image clearly and to return to it again and again through the struggles that may lie ahead.