[7] This is referring to what is known as the Battle of the Trench or the Confederates which occurred in 5 A.H./627 C.E., where the pagans of Makkah along with some Arab and Jewish tribes (totaling around 10,000 soldiers) besieged Madinah, and the Prophet (ﷺ) positioned around 3000 soldiers to defend Madinah. The Prophet (ﷺ) had anticipated the offense and, upon advice from one of his companions, Salmān from Persia, dug a trench around the city to protect it from the invaders. After several attempts to cross the trench, the Allied forces lost morale and were forced to end the siege due to severe weather conditions. By this Allah saved Muslims from the machination of the non-Muslim allied forces to destroy the newly-born Islamic community in Madinah.
[8] i.e., the angles.