Asma’ sent me to 'Abdullah bin 'Umar, and she said: I have heard that you regard three things as haram: borders on garments, saddle cloths made of bright red cloth, and fasting the whole of Rajab. 'Abdullah said to me: As for what you have mentioned about Rajab, what about one who fasts continually? As for what you said about borders on garments, I heard 'Umar bin al-Khattab say: I heard the Messenger of Allah ﷺ say: “Whoever wears silk in this world will not wear it in the Hereafter."