So they [Ya’juj and Ma’juj (Gog and Magog)] were made powerless to scale it or dig through it.
Meaning:-
Story of Yajooj and Majooj – The Gog and Magog
God created a nation called Ya’jooj and Ma’jooj. In the beginning they were free. King Zulqarnian imprisoned up behind a wall. They are still imprisoned today, and will be freed near the Day of Judgement. They will come out and create a lot of trouble. Their population is ten times larger than the world’s population.