They will make war on the Lamb, and the Lamb will conquer them, for he is Lord of lords and King of kings, and those with him are called and chosen and faithful. (Revelation 17:14)
This verse (written around late 63AD) forms part of the context for the events about to occur with the ending of the Old Covenant
elements (the Temple, the Priesthood, and the Sacrificial system of Law). The events leading up to the close of the Old Covenant are referred to in the New Testament as "the last days" (eg. Hebrews 1:2) or "the end of the ages" (eg. 1Cor. 10:11; Hebrews 9:26). Revelation 17:14 describes the Conquering Christ who overcomes all opposition to Him, His Cause, and His people.
When someone has the ability to achieve their predetermined will and plan with exact precision by integrating all of the variables circumstances, free-will agents, and even disobedience, we refer to this phenomenon as "sovereignty".
This verse in Revelation is a clear statement of Christ's sovereignty. He is "Lord of lords and King of kings". He will always achieve His predetermined will and plan. And this applies no more powerfully in His plan of salvation. For those He saves are - "called", "chosen" and enabled by Him to be "faithful".
Thank God for His sovereign grace!