The Bible does not say that Abraham felt that if he obeyed, in a mere few hours, a day, or a week, Isaac would come back to life.
فَهُو لَمْ يَعْرِفْ مَتَى سَيَقُومُ ،‏ لٰكِنَّهُ وَثِقَ أَنَّ يَهْوَهَ سَيُعِيدُهُ إِلَى ٱلْحَيَاةِ .‏