The words "Ghabiya", and "Ghumma", both have the same meanings, namely clouded sky or sky overcast with clouds, as a result of which the moon is not visible. In that case, the injunction is that thirty days of the month be completed. If the moon of Ramadan is not sighted on the 29th Sha`ban, then its thirty days be completed and Ramadan's Saum be started on the next day. Similarly, if the moon for the month of Shawwal is not sighted on the 29th of Ramadan, thirty days of Saum must be completed before celebrating `Eid-ul-Fitr. This means that the sighting of the moon is necessary for keeping the Saum of Ramadan. Counting by celestial system is not sufficient for this purpose. Moreover, the evidence of reliable witnesses for the crescent of Ramadan and the evidence of two dependable witnesses for the crescent of Shawwal are sufficient. This amount of evidence will fulfill the requirement of sighting the moon. Whether the sighting of the moon at one place is sufficient for another place is controversial and arguments of both the groups of `Ulama', who support and oppose it, are based on this Hadith. The group which contend that the sighting of the moon at one place is valid for another holds that the words "Sumu" and "Aftiru" are addressed to all the Muslims, and for this reason the sighting at one place holds good for another place. The group which holds that the sighting of the moon at one place is not enough for the Muslims of other localities contend that the words are addressed to the people who have actually sighted the moon. The Muslims of the localities of other areas who have not sighted the moon are not addressed by these words. They say that the sighting of the moon goes with each area according to which they will decide about starting of Saum and celebrating `Eid. There is a third group also, which is of the opinion that for such areas which are in close proximity and do not have much difference in the timings of sunrise and sunset, the sighting of the moon at one place holds good for the other. In any case, it is a moderate view, which can be implemented without fear of its being wrong. According to this view, at least in one country the sighting of the moon at one place holds good for all other areas.