Hazrat Abdullah bin Abbas narrates from Hazrat Ka'b that he said: When you see that rain has been withheld, then know that people have withheld zakat, so Allah Almighty has withheld what He had (i.e., rain). And when you see that swords have been unsheathed, then know that the command of Allah Almighty is being neglected, so they begin to take revenge on one another. And when you see that adultery has become widespread, then know that usury has spread.