Al-Anfal 8:42 اذ انتم بالعدوة الدنيا وهم بالعدوة القصوى والركب اسفل منكم ولو تواعدتم لاختلفتم في الميعاد ولاكن ليقضي الله امرا كان مفعولا ليهلك من هلك عن بينة ويحيى من حي عن بينة وان الله لسميع عليم ٤٢

When ye were on the near bank (of the valley) and they were on the yonder bank, and the caravan was below you (on the coast plain). And had ye trysted to meet one another ye surely would have failed to keep the tryst, but (it happened, as it did, without the forethought of either of you) that Allah might conclude a thing that must be done; that he who perished (on that day) might perish by a clear proof (of His Sovereignty) and he who survived might survive by a clear proof (of His Sovereignty). Lo! Allah in truth is Hearer, Knower.