"Of the dragon, the ancient serpent, it is expressly said that he is Satan. And he was now bound by the angel for a thousand years. Let us place this picture before us vividly, for John says he saw it; we therefore can also form a living mental image of the same. Therefore, right before his eyes, while John was viewing the picture, the dragon, namely the devil, was actually being bound by the angel with the chain, so that he could neither stir nor move. This John sees! The fact that the dragon was bound a thousand years could naturally only be communicated to John as information revealed within himself by the Spirit; for the picture did not last a thousand years. I have experienced the same thing when the Lord has spoken to me in a dream or a vision and I simply knew or inherently understood something about the vision that was not communicated to me by anything I saw in the scenes shown me. If we ask — Was Satan actually being bound at the precise moment in which John saw this? Our answer is — No! For John was not being shown a one-time event to transpire in the spirit-realm, either past or future, but he was shown a great spiritual reality to be experienced in all of the Lord’s people as they walk in the spirit and grow up into Christ. It was just a symbolic picture of that. And the thing that matters concerning the picture, in so far as it is a revelation of God’s working within us, is not just the binding itself, but the binding for a thousand years! The deep mystery is that this reveals to us not only the fact of Satan being totally bound in the abyss of our earth, within our heart, but also the HOW of that binding!"

Much more in the link:

https://www.godfire.net/eby/rev219.html

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