Rav Ketina happened once, in his travels, to hear the noise of an
earthquake just as he came opposite to the abode of one who was wont to
conjure with human bones. Happening to mutter aloud to himself as he
passed, "Does the conjurer really know what that noise is?" a voice
answered, "Ketina, Ketina, why shouldn't I know? When the Holy
One--blessed be He!--thinks of His children who dwell in sorrowful
circumstances among the nations of the earth, He lets fall two tears
into the great sea, and His voice is heard from one end of the world to
the other, and that is the rumbling noise we hear." Upon which Rav
Ketina protested, "The conjurer is a liar, his words are not true; they
might have been true, had there been two rumbling noises." The fact was,
two such noises were heard, but Rav Ketina would not acknowledge it,
lest, by so doing, he should increase the popularity of the conjurer.
Rav Ketina is of the opinion that the rumbling noise is caused by God
clapping His hands together, as it is said (Ezek. xxi, 22; A.V., ver.
17), "I will also smite My hands together, and I will cause My fury to
rest."

THE TALMUD, _Berachoth_, fol. 59, col. 1.