Here and in Daniel Dan. 12:1, the angels swear to underscore the unchangeable nature of the message they give. In both cases, the aspect of the message being emphasized is the timing with which prophesied events will take place. Daniels angel indicated that the final period when the power of Israel would be shattered would be times, time and half a time (Dan. Dan. 12:7). Here, the angel tells John that the long history of delay where Gods grace prevented Him from moving in final judgment has come to an end. See Divine Similarities. There is no higher person by which one can swear than the eternal God (Rev. Rev. 1:18+; Rev. 4:9+).
who created heaven and . . . the earth and . . . the sea
Emphasis is placed upon the identity of God as Creator, for the declaration of the angel in this chapter is intimately connected with God repossessing the title to the earth (both land and sea, indeed the entire creation), which has been marred by the interposition of sin and Satan. Mention of Gods creative acts over both the earth and sea parallels his stance (Rev. Rev. 10:2+). God owns that which He has created (Gen. Gen. 2:1; 1Cor. 1Cor. 10:26)! See commentary on Revelation 4:11.
there should be delay no longer
χρόνος οὐκέτι ἔσται [chronos ouketi estai] , time no longer it will be. Rev. 6:10+) for the accomplishment of Gods covenanted and promised purposes.1 The truth of this statement is found in the response of the devil after having been cast to earth (Rev. Rev. 12:12+). Although prophetic events such as the coming of Christ for His church and the Day of the Lord are Imminentthey could begin at any timehistory has evidenced a delay in the consummation of things:
The true attitude of the Church, and that to which all the representations and admonitions of the Scriptures are framed, is to be looking and ready any day and every day for the coming of Christ to seize away his waiting and watching saints. But in faithfully assuming this attitude, and thus hoping and expecting the speedy fulfilment of what has been promised, the Church has been made to see one notable and quickening period after another pass away without bringing the consummation which was anticipated. Eve thought the promise on the point of fulfilment when Cain was born; but He whom she was expecting was yet 4,000 years away. When Simeon took the infant Savior to his bosom . . . he supposed that the time for the consummation had arrived; but it was only the preliminary advent that he had lived to witness. . . . The early Christians were lively in their expectations that yet in their day the standard of the coming One would be seen unfurled in the sky, and all their hopes be consummated; but the days of the Apostles and of the apostolic fathers passed, and still the Bridegroom tarried. . . . Although the Saviour may come any day, and our duty is to be looking for Him every day, it is still possible that all present prognostications on the subject may fail, as they have always failed; that years and years of earnest and confident expectation may go by without bringing the Lord from heaven; and that delay after delay, and ever repeating prolongations of the time of waiting may intervene, till it becomes necessary for the preservation of the faith of Gods people to hear the fresh edict from the lips of their Lord, that there shall be no more delay. Though the coming of the consummation be slow, it will come. There is not another truth in Gods word that is so peculiarly authenticated. . . . Shall we then have any doubt upon the subject? Shall we allow the failure of mens figures and prognostications to shake our confidence or obscure our hope? Shall we suffer the many and long delays that have occurred, or that ever may occur, to drive us into the scoffers ranks?2Habakkuk set forth the principle of the patience that is needed in regard to prophetic pronouncements of God: For the vision is yet for an appointed time; but at the end it will speak, and it will not lie. Though it tarries, wait for it; because it will surely come, it will not tarry (Hab. Hab. 2:3). Gods prophetic timetable is not ours. How often we forget! The result is the discrediting of His Holy Word as we misrepresent that which it teaches by making it conform to our own expectations concerning the age within which we find ourselves in the plan of history. But we must be patient! Gods predictions are sure, but they are for an appointed time which He alone knows. Let us remember that! That which God has predicted He will manifest in His own time [emphasis added] (1Ti. 1Ti. 6:15).
2 J. A. Seiss, The Apocalypse: Lectures on the Book of Revelation (Grand Rapids, MI: Zondervan Publishing House, 1966), Rev. 10:6.