Thou wouldst have thought them awake, as they lay sleeping, while We turned them now to the right, now to the left,' and their dog 'stretching its paws on the threshold. Hadst thou observed them surely thou wouldst have turned thy back on them in flight, and been filled with terror of them. 18 And in like manner We awakened them that they might question one another. A speaker from among them said: How long have ye tarried? They said: We have tarried a day or some part of a day, (Others) said: Your Lord best knoweth what ye have tarried. Now send one of you with this your silver coin unto the city, and let him see what food is purest there and bring you a supply thereof. Let him be courteous and let no man know of you. 19 For if they should come upon us, they will stone us to death or force us to revert to their faith whereafter we shall never prosper." 20 And even so We made them stumble upon them, that they might know that God's promise is true, and that the Hour -- there is no doubt of it. When they were contending among themselves of their affair then they said, 'Build over them a building; their Lord knows of them very well.' Said those who prevailed over their affair, 'We will raise over them a place of worship.' 21 (They will say, 'Three; and 'their dog was the fourth of them.' They will say, 'Five; and their dog was the sixth of them, guessing at the Unseen. They will say, 'Seven; and their dog was the eighth of them.' Say: 'My Lord knows very well their number, and none knows them, except a few.' So do not dispute with them, except in outward disputation, and ask not any of them for a pronouncement on them. 22