It is written in Hujjat-ullahi ’alal’alamin, “People called Ya’juj and Ma’juj are descendants of Yafas (Japheth), the (third) son of Nuh (Noah) ‘alaihissalam’. They have flat and wide faces, small eyes and big ears, and they are short. Each has a thousand children. Nine - tenths of the number of genies and men are Ya’juj and Ma’juj. Every day they make a hole in the wall they have been left behind. But at night the wall becomes the same as it was before. They are unbelievers. When they get beyond the wall, they will attack people. People will take refuge in cities and in buildings. They will eat up animals and drain rivers. Isa ‘alaihissalam’ and his Sahaba  will invoke against them. A wound will appear on the neck of each, and they will all die in one night. Eating them, animals will multiply. Their stink will make the earth impossible to live on.”
It is written in the Qur’an that Gog and Magog are two evil peoples which were left behind a wall at a very ancient time and that they will spread on the earth towards Doomsday. Considering that archaelogical research discovers cities buried under the ground and sea fossils on the peaks of mountains, that wall does not have to be in the open, nor do those people have to be numerous today. As a matter of fact, it could be thought that as thousands of millions of people today have originated from two people, so those two peoples will spread on the earth by multiplying out of a few people and none knows where these people are.
The beast called Dabbatulard will appear, the sky will be covered with smoke, which will reach all the people and will hurt them; due to its pain everybody will pray, “Ya Rabbi! Remove this torment from us. We now believe in Thee!” The last symptom is a fire, which will break out in Aden [which is in Yemen].
 Sahaba: if a Muslim has seen the Prophet, or talked to him, at least once when the Prophet was alive, he is called Sahabi. Plural form of Sahabi is Sahaba or As’hab. The word Sahaba-i kiram includes all those great people each of whom has seen the Prophet at least once. The lowest of the Sahaba is much higher than the highest of other Muslims. If a person has not seen the Prophet but has seen or talked to one of the Sahaba at least once, he is called Tabi’. Its plural form is Tabi’in. In other words, the Tabi’in are the successors of the Sahaba. If a person has not seen any of the Sahaba but has seen at least one of the Tabi’in, he is called Taba’i Tabi’in. The Sahaba, the Tabi’in and the Taba’i tabi’in altogether are called the Salaf-i salihin (the early savants).