Musnad Ishaq

Benefits:
Yajuj and Majuj (Gog and Magog) are a corrupting people, and at the request of the people of that land, in order to protect them from their evil, Sayyiduna Dhul-Qarnayn constructed a great barrier and confined them, as mentioned in (Surah al-Kahf, verses 93–99). Near the Day of Judgment, they will be released and will attack the entire world. Allah the Exalted says:

﴿حَتّٰٓی اِذَا فُتِحَتْ یَاْجُوْجُ وَ مَاْجُوْجُ وَ هُمْ مِّنْ کُلِّ حَدَبٍ یَّنْسِلُوْنَ() وَ اقْتَرَبَ الْوَعْدُ الْحَقُّ فَاِذَاهِیَ شَاخِصَةٌ اَبْصَارُ الَّذِیْنَ کَفَرُوْا یٰوَیْلَنَا قَدْ کُنَّا فِیْ غَفْلَةٍ مِّنْ هٰذَا بَلْ کُنَّا ظٰلِمِیْنَ﴾ (al-Anbiya: 96–97)

"Until, when Gog and Magog are let loose and they rush forth from every elevation, and the true promise draws near, then behold! The eyes of those who disbelieved will be fixed in horror. (They will say:) 'Woe to us! We were indeed heedless of this; nay, we were wrongdoers.'"

It is mentioned in Sahih Muslim that in the presence of Sayyiduna Isa (alayhis salam), Yajuj and Majuj will emerge. The gesture for "ten" is made by placing the tip of the thumb on the tip of the index finger. The meaning is that the hole that has appeared in the wall is as large as the circle formed by placing the thumb on the index finger. Once a hole appears, there is the danger that it will become larger, and eventually that wall will break down.