Iron Made Soft

Allah (swt) also gave him another miracle: iron, steel, would become soft in his hands; he could move it however he wished. Wa alannā lahu al-ḥadīd — We made iron soft in his hands. Humans in that time had iron, but the process of making tools out of it was very difficult and time-consuming. Allah (swt) made iron soft in the hands of Dāwūd; he would mould it however he wanted.

Allah (swt) then taught him how to make shields, armour, out of steel in a new way; it was a new invention. Before that, they would make armour in the form of iron plates, which were solid. So the soldier would have to wear that heavy iron plate, which has two downsides to it. First of all, it is heavy. The second downside is that it prevents flexibility of movement, because it is a solid plate of iron, of steel. Allah (swt) taught Dāwūd how to make armour out of rings of iron: he would make the iron into rings, and attach the rings together, and attach rings to those rings, until he made armour that would cover the body. And this eliminates the two downsides of the other armour, because it is very light in weight — rings are very light — and it is very flexible, because it is rings; you can move freely. But it offers the same protection, because it is made of iron.

Allah (swt) says: wa ʿallamnāhu ṣanʿata labūsin lakum — We taught him the making of metal coats. Allah (swt) taught him how to make these metal coats. Li-tuḥṣinakum min baʾsikum — so that it will protect you in your fighting. Allah is the One who taught him how to do this.

In the other ayah Allah (swt) says: ani ʿmal sābighātin wa qaddir fī al-sard — make full coats of mail, balancing well the rings of chain armour, and work righteously; truly, I am All-Seer of what you do. Wa qaddir fī al-sard — Allah (swt) is telling Dāwūd (peace be upon him): make the rings proportionate. Do not make them too large, because if they are too large they could be penetrated; and if they are too small, there could be other negative aspects to it. So Allah (swt) is telling Dāwūd (peace be upon him): make them the right size.