Then rush thereby upon an assembly…” إِنَّ الْإِنْسَانَ...
Shaykh Mufeed has narrated with regard to the expedition of Zatul Salasil that one day a desert Arab came to the Prophet and reported that a party of Arabs had gathered in Ramal Valley and made an agreement to attack Medina. The Holy Prophet (S) collected the Muslims and told them that a party of disbelievers has plotted to attack them and they must be prepared to defend themselves. Ashab Suffa volunteered in sincerity.
The Holy Prophet (S) drew lots from the eighty persons and appointed Abu Bakr as their chief and gave him the standard, instructing him to punish the Bani Sulaym. Idolaters had appointed watches on mountain peaks. Since Abu Bakr traveled by the highway he was at once detected and they armed themselves. When Abu Bakr reached the heavily wooded and rocky land and the infidels lived in a valley that was difficult to enter.
When Abu Bakr attempted to enter it, the disbelievers came out and slain many Muslims. At last Abu Bakr had to return unsuccessful from there. Then the Messenger of Allah (S) gave the standard to Umar and sent him on the same expedition. He also followed the usual route and was soon detected by the disbeliever who hid beneath the trees and rocks. When Umar stepped into their valley, they came out and drove him away. When he also returned unsuccessful; the Holy Prophet (S) was extremely aggrieved.