Experience. How did Abraham acquire experience that strengthened his faith in Jehovah?
فَقَدْ أَيْقَنَ إِبْرَاهِيمُ أَنَّ إِطَاعَةَ ٱللهِ سَتَعُودُ بِٱلْبَرَكَاتِ عَلَيْهِ وَعَلَى ٱبْنِهِ ٱلْحَبِيبِ .‏