Abdullah ibn Abbas RA says:
"Rasulullah SAW was the most generous among people in performing good deeds (- no one could compare with him in generosity. He himself led a simple life, but in giving he would put a king to shame. At a time of great need a woman presented him a sheet, and he wore it as he was in need of it. A person came to him, and asked him for it, he presented the sheet to that person. Taking of loans and fulfilling the needs of others, when the creditors came, and if something had come from somewhere, he would pay the debts, and did not go home till everything was given to the needy. There exists many incidents of this nature, so much so that it is not possible to enumerate them). Particularly in the month of Ramadhan, he would be more generous till the month ended. (His generosity in this month exceeded all the other months). In this month when Jibril AS came and recited the Qur'an to Rasulullah SAW, at that time his generosity exceeded the wind that brings forth heavy rains."
Here the wind is described with speed, that the wind did not blow as fast, as did the generosity of Rasulullah SAW, or it is his widespread benefits, the benefits of rain are not so widespread, as that of Rasulullah SAW. The example of rain is just to illustrate, otherwise what connection has the rain with the generosity of Rasulullah SAW, as the rain only benefits in the growing of material things. The shower of Rasulullah SAW benefits materially, spiritually, worldly and religiously. Rain gives life to the earth, and he (SAW) gave life to the hearts.
It is narrated in Tirmidhi that once there came for Rasulullah SAW, ninety thousand Dirhams, the equivalent of which is even a large amount in this day and age. Rasulullah SAW had the amount spread onto a sack, and had it distributed there and then. A person later came; and Rasulullah SAW said to him, I have nothing left by me. You may loan from someone on my behalf, when I have something I shall pay that debt. Such was the noble habit of Rasulullah SAW. What can one ask regarding this in the month of Ramadhan. It was a time when from the Lord of all the Heavens, the best words were revealed at the best time, to the best of the creation by the angels. Rasulullah SAW was blessed with the highest and complete rank; and the highest rank is to have the qualities of Allah the Almighty.