"‏ لَمَّا خَلَقَ اللَّهُ الأَرْضَ جَعَلَتْ تَمِيدُ فَخَلَقَ الْجِبَالَ فَعَادَ بِهَا عَلَيْهَا فَاسْتَقَرَّتْ فَعَجِبَتِ الْمَلاَئِكَةُ مِنْ شِدَّةِ الْجِبَالِ قَالُوا يَا رَبِّ هَلْ مِنْ خَلْقِكَ شَيْءٌ أَشَدُّ مِنَ الْجِبَالِ قَالَ نَعَمِ الْحَدِيدُ ‏.‏ قَالُوا يَا رَبِّ فَهَلْ مِنْ خَلْقِكَ شَيْءٌ أَشَدُّ مِنَ الْحَدِيدِ قَالَ نَعَمِ النَّارُ ‏.‏ فَقَالُوا يَا رَبِّ فَهَلْ مِنْ خَلْقِكَ شَيْءٌ أَشَدُّ مِنَ النَّارِ قَالَ نَعَمِ الْمَاءُ ‏.‏ قَالُوا يَا رَبِّ فَهَلْ مِنْ خَلْقِكَ شَيْءٌ أَشَدُّ مِنَ الْمَاءِ قَالَ نَعَمْ الرِّيحُ قَالُوا يَا رَبِّ فَهَلْ مِنْ خَلْقِكَ شَيْءٌ أَشَدُّ مِنَ الرِّيحِ قَالَ نَعَمِ ابْنُ آدَمَ تَصَدَّقَ بِصَدَقَةٍ بِيَمِينِهِ يُخْفِيهَا مِنْ شِمَالِهِ ‏"

The Prophet said: “When Allah created the earth, it started shaking. So He created the mountains, and said to them: ‘Upon it’ so it began to settle. The angels were amazed at the strength of the mountains, so they said: ‘O Lord! Is there among your creatures one who is more severe than the mountains?’ He said: ‘Yes. Iron.’ They said: ‘O Lord! Then is there anything among your creatures that is more severe than that iron?’ He said: ‘Yes. Fire.’ So they said: ‘O Lord! Is there anything among your creatures that is more severe than fire?’ He said: ‘Yes. Water.’ They said: ‘O Lord! Is there anything among your creatures that is more severe than water?’ He said: ‘Yes. Wind.’ They said: ‘O Lord! Is there anything among your creatures more severe than wind?’ He said: ‘Yes. The son of Adam. He gives charity with his right hands, while hiding it from his left.’”