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 thus did We rouse them that they might question each other. A speaker among them said: How long have you tarried? They said: We have tarried for a day or a part of a day. (Others) said: Your Lord knows best how long you have tarried. Now send one of you with this silver (coin) of yours to the city, then let him see which of them has purest food, so let him bring you provision from it, and let him behave with gentleness, and by no means make your case known to any one: 19 for if they find you out, they will stone you to death, or force you back into their faith. In that case you would never prosper." 20 And thus did We make (men) to get knowledge of them that they might know that Allah's promise is true and that as for the hour there is no doubt about it. When they disputed among themselves about their affair and said: Erect an edifice over them-- their Lord best knows them. Those who prevailed in their affair said: We will certainly raise a masjid over them. 21 (Some) say they were three, the dog being the fourth among them; (others) say they were five, the dog being the sixth,- doubtfully guessing at the unknown; (yet others) say they were seven, the dog being the eighth. Say thou: "My Lord knoweth best their number; It is but few that know their (real case)." Enter not, therefore, into controversies concerning them, except on a matter that is clear, nor consult any of them about (the affair of) the Sleepers. 22