«كان إذا استراث الخبر تمثل ببيت طرفة: ويأتيك بالأخبار من لم تزود»
It was the practice of the Prophet (peace and blessings be upon him):
"When news was slow in coming to him (peace and blessings be upon him), he would recite this verse of Tarafah (the poet): 'The one you did not provision (to bring news) will bring you the news.'"
Hadith Referenceصحیح الجامع الصغیر / حرف الكاف / 4665