| Clarke's Commentary on the Bible I will execute vengeance - upon the heathen - And he did so; for the empires of the Assyrians, Chaldeans, and others, the sworn enemies of the Jews, have long since been utterly destroyed.
Gill's Exposition of the Entire BibleAnd I will execute vengeance in anger, and fury upon the Heathen,.... Or "nations" (o); not the Pagan nations only, but the Papal and Mahometan ones, even all that are enemies to Christ, and his church and people: such as they have not heard; such terrible judgments, and dreadful expressions of divine wrath and fury, by earthquakes, hailstones, &c. as were never known or heard of in the world before; see Revelation 16:18; or, "which have not heard" (p); the people that have not heard and hearkened to the word of God, to the voice of Christ in the Gospel, but have turned a deaf ear to it, and despised it. So the Targum, "who have not received the doctrine of the law;'' but it is much more agreeable to understand it of the doctrine of the Gospel disobeyed by men, and therefore justly punished; see 2 Thessalonians 1:8. (o) "gentes", Junius & Tremellius. (p) "quae non audierunt", Pagninus, Montanus; "quae non auscultaverint", Junius & Tremellius; "quae non obediverunt", Burkius.
Geneva Study BibleAnd I will execute vengeance in anger and fury upon the heathen, {l} such as they have not heard. (l) It will be so terrible that nothing like it has been heard of.
Wesley's Notes 5:15 Have not heard - In an unprecedented manner. Christ will give his Son either the hearts or necks of his enemies, and make them either his friends or his footstool.
Jamieson-Fausset-Brown Bible Commentary15. vengeance . such as they have not heard-or, as the Hebrew order favors, "the nations that have not hearkened to My warnings." So the Septuagint (Ps 149:7).
Matthew Henry's Concise Commentary5:7-15 The remnant of Israel, converted to Christ in the primitive times, were among many nations as the drops of dew, and were made instruments in calling a large increase of spiritual worshippers. But to those who neglected or opposed this salvation, they would, as lions, cause terror, their doctrine condemning them. The Lord also declares that he would cause not only the reformation of the Jews, but the purification of the Christian church. In like manner shall we be assured of victory in our personal conflicts, as we simply depend upon the Lord our salvation, worship him, and serve him with diligence. | 
