and most necessary sign of His coming on those who had believed, that every one of them spoke in the tongues of all nations; thus signifying that the unity of the catholic Church would embrace all nations, and would in like manner speak in all tongues. 50. _Of the preaching of the gospel, which is made more famous and powerful by the sufferings of its preachers._ Then was fulfilled that prophecy, "Out of Sion shall go forth the law, and the word of the Lord out of Jerusalem;"[600] and the prediction of the Lord Christ Himself, when, after the resurrection, "He opened the understanding" of His amazed disciples "that they might understand the Scriptures, and said unto them that thus it is written, and thus it behoved Christ to suffer, and to rise from the dead the third day, and that repentance and remission of sins should be preached in His name among all nations, beginning at Jerusalem."[601] And again, when, in reply to their questioning about the day of His last coming, He said, "It is not for you to know the times or the seasons which the Father hath put in His own power; but ye shall receive the power of the Holy Ghost coming upon you, and ye shall be witnesses unto me both in Jerusalem, and in all Judea, and Samaria, and even unto the ends of the earth."[602] First of all, the Church spread herself abroad from Jerusalem; and when very many in Judea and Samaria had believed, she also went into other nations by those who announced the gospel, whom, as lights, He Himself had both prepared by His word and kindled by His Holy Spirit. For He had said to them, "Fear ye not them which kill the body, but are not able to kill the soul."[603] And that they might not be frozen with fear, they burned with the fire of charity. Finally, the gospel of Christ was preached in the whole world, not only by those who had seen and heard Him both before His passion and after His resurrection, but also after their death by their successors, amid the horrible persecutions, diverse torments and deaths of the martyrs, God also bearing them witness, both with signs and wonders, and divers miracles and gifts of the Holy Ghost,[604] that the people of the nations, believing in Him who was crucified for their redemption, might venerate with Christian love the blood of the martyrs which they had poured forth with devilish fury, and the very kings by whose laws the Church had been laid waste might become profitably subject to that name they had cruelly striven to take away from the earth, and might begin to persecute the false gods for whose sake the worshippers of the true God had formerly been persecuted. 51. _That the catholic faith may be confirmed even by the dissensions of the heretics._