ruler of all: God as the one who actually holds every power and every event in his control
This is a title for God, not a general adjective. In the New Testament it appears ten times: once inside a chain of Old Testament quotations in 2 Corinthians, and nine times in Revelation, where it is the book's standing name for God. In every case it refers to God the Father.
The Greek word joins "all" to a family of words that covers both might and mastery, the sense of holding something firmly in hand. Which side you hear changes the claim: raw ability to do anything, or rule actually being exercised over everything there is. Most scholars now hear the second. The title says that history is in God's hands right now, not merely that God could act if he chose.
It reached the New Testament through the Greek Old Testament, where it does duty for two Hebrew titles: "the LORD of hosts", built on the word for armies (צָבָא), and the ancient name for God that Job uses again and again (שַׁדַּי). A commander of armies became a ruler of all things, and that shift is most of what the Greek word carries into Revelation.
In Revelation the title turns up in three settings, and together they show what it is for:
- in the songs of heaven, where God is praised as the one who has begun to reign
- in God's own opening declaration, beside the promise that he is the one who is and was and is coming
- in the scenes of judgment, where that rule is pressed against everything resisting it
Underneath all three is a contest over who actually runs the world. Revelation hands God a title that the empires of the day wanted for their own rulers, and it uses a different word for the hostile powers that grip this age (κοσμοκράτωρ).
Disputed
Whether the word names God's actual exercise of rule over all things or God's abstract capacity to do anything.
- majorityIt names rule actually exercised over all things, and later metaphysical omnipotence should not be read back into it.; Wilhelm Michaelis, "κράτος, κρατέω, κραταιός, κοσμοκράτωρ, παντοκράτωρ," Theological Dictionary of the New Testament, vol. 3 (Eerdmans, 1965), 914-15; Richard Bauckham, The Theology of the Book of Revelation (Cambridge University Press, 1993), 30-35; Reinhard Feldmeier and Hermann Spieckermann, God of the Living: A Biblical Theology (Baylor University Press, 2011), ch. 5
- minorityThe Greek genuinely holds both notes together, and narrowing it to rule alone loses its claim about God's power itself.; BDAG, s.v. παντοκράτωρ; Craig R. Koester, Revelation, Anchor Yale Bible 38A (Yale University Press, 2014)