Tafsir of Al-Waqi'ah 56:72

Is it you who made the tree thereof to grow, or are We the Grower? meaning, `rather We have made kindling fire possible.' The Arabs had two kinds of trees called Al-Markh and Al-`Afar (that they used to ignite a fire). When they would rub a green branch from each of these two trees against each other, sparkles of fire would emit from them. Allah's statement,