George Haydock's Catholic Bible Commentary - Revelation 6:12
At the opening of the sixth seal....a great earthquake, &c. Many think that these dreadful signs, of the sun turning black, &c. are not to happen till the time of antichrist, a little before the end of the world. See Matthew xiv.; Luke xxi.; Isaias xiii. and xxxiv.; Ezechiel xxxiii.; Daniel xii.; &c. Others apply these prodigies to God's visible chastisements, on the heathen emperors and persecutors of the Christians, before the first Christian emperor Constantine. (Witham) --- ... read more
Hawker's Poor Man's Commentary - Revelation 6:12-17
(12) And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood; (13) And the stars of heaven fell unto the earth, even as a fig tree casteth her untimely figs, when she is shaken of a mighty wind. (14) And the heaven departed as a scroll when it is rolled together; and every mountain and island were moved out of their places. (15) And the kings of the earth, and the great men, and the rich... read more