The word(s) "four" appears 18 time(s) in 17 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) Those who swear that they will not go in to their wives should wait four months; so if they go back, then Allah is surely Forgiving, Merciful.

(2) And (as for) those of you who die and leave wives behind, they should keep themselves in waiting for four months and ten days; then when they have fully attained their term, there is no blame on you for what they do for themselves in a lawful manner; and Allah is aware of what you do.

(3) And when Ibrahim said: My Lord! show me how Thou givest life to the dead, He said: What! and do you not believe? He said: Yes, but that my heart may be at ease. He said: Then take four of the birds, then train them to follow you, then place on every mountain a part of them, then call them, they will come to you flying; and know that Allah is Mighty, Wise.

(4) And if you fear that you cannot act equitably towards orphans, then marry such women as seem good to you, two and three and four; but if you fear that you will not do justice (between them), then (marry) only one or what your right hands possess; this is more proper, that you may not deviate from the right course.

(5) And you shall have half of what your wives leave if they have no child, but if they have a child, then you shall have a fourth of what they leave after (payment of) any bequest they may have bequeathed or a debt; and they shall have the fourth of what you leave if you have no child, but if you have a child then they shall have the eighth of what you leave after (payment of) a bequest you may have bequeathed or a debt; and if a man or a woman leaves property to be inherited by neither parents nor offspring, and he (or she) has a brother or a sister, then each of them two shall have the sixth, but if they are more than that, they shall be sharers in the third after (payment of) any bequest that may have been bequeathed or a debt that does not harm (others); this is an ordinance from Allah: and Allah is Knowing, Forbearing.

(6) And as for those who are guilty of an indecency from among your women, call to witnesses against them four (witnesses) from among you; then if they bear witness confine them to the houses until death takes them away or Allah opens some way for them.

(7) So go about in the land for four months and know that you cannot weaken Allah and that Allah will bring disgrace to the unbelievers.

(8) Surely the number of months with Allah is twelve months in Allah's ordinance since the day when He created the heavens and the earth, of these four being sacred; that is the right reckoning; therefore be not unjust to yourselves regarding them, and fight the polytheists all together as they fight you all together; and know that Allah is with those who guard (against evil).

(9) (Some) say: (They are) three, the fourth of them being their dog; and (others) say: Five, the sixth of them being their dog, making conjectures at what is unknown; and (others yet) say: Seven, and the eighth of them is their dog. Say: My Lord best knows their number, none knows them but a few; therefore contend not in the matter of them but with an outward contention, and do not question concerning them any of them.

(10) And those who accuse free women then do not bring four witnesses, flog them, (giving) eighty stripes, and do not admit any evidence from them ever; and these it is that are the transgressors,