Why does the Qur'an describe mountains as pegs (awtād)?

Answer

In verse 78:7, Allah says, "and the mountains as pegs (awtād)." The classical commentators explain awtād by analogy to tent-stakes: just as pegs hold a tent firm, the mountains were set in the earth to steady it. Al-Saʿdī and Ibn Kathīr both say the mountains anchor the earth so it does not sway or quake with its inhabitants, while al-Ṭabarī and al-Qurṭubī give the lexical sense of awtād as stakes driven down to fix something in place. The image is functional and evocative, conveying stability and God's provision rather than offering a geological theory. Many readers note that this language of mountains "steadying" the earth resonates with the modern understanding that large mountain ranges have deep crustal roots and participate in isostatic balance — mountains extend below the surface, not just above it. This resonance is worth appreciating, but the verse's primary purpose is to list a sign of divine wisdom: the One who fixed the mountains for human benefit is the same One who can raise the dead, which is the surah's central argument.