This excerpt is taken from Sheikh Abi Abdul Saboor Abdul Ghafoor Damni's book Fazail al-Jihad.
عن أنس بن مالك قال بعث رسول الله صلى الله عليه وسلم بسيسة عينا ينظر ما صنعت عير أبى سفيان فجاء وما فى البيت غيري وغير رسول الله صلى الله عليه وسلم (قال ما أدري ما استثنى بعض نسائه) قال فحدث الحديث قال فخرج رسول الله صلى الله عليه وسلم فتكلم فقال إن لنا طلبة فمن كان ظهره حاضرا فليركب معنا فجعل الرجال يستأذنونه فى ظهرانيهم فى علو المدينة فقال لا إلا من كان ظهره حاضرا فانطلق رسول الله صلى الله عليه وسلم وأصحابه حتى سبقوا المشركين إلى بدر وجاء المشركون فقال رسول الله صلى الله عليه وسلم لا يقدمن أحد منكم إلى شيء حتى أكون أنا دونه فدنا المشركون فقال رسول الله صلى الله عليه وسلم قوموا إلى جنة عرضها السموات والأرض قال يقول عمير بن الحمام الأنصاري يا رسول الله جنة عرضها السموات والأرض قال نعم، قال بخ بخ فقال رسول الله صلى الله عليه وسلم ما يحملك على قولك بخ بخ قال لا والله يا رسول الله إلا رجاءة أن أكون من أهلها قال فإنك من أهلها فأخرج تمرات من قرنه فجعل يأكل منهن ثم قال لئن حييت حتى آكل تمراتي هذه إنها لحياة طويلة قال فرمى بما كان معه من التمر ثم قاتلهم حتى قتل.
"Anas رضي الله عنه narrates that the Messenger of Allah صلى الله عليه وسلم sent Buseesa (the name of a companion) as a spy. He brought news of Abu Sufyan's caravan. When he came, (Anas رضي الله عنه says) at that time, there was no one in the house except me and the Messenger of Allah صلى الله عليه وسلم. The narrator states that he does not remember Anas رضي الله عنه mentioning any wife of the Prophet صلى الله عليه وسلم, then he narrated that the Messenger of Allah صلى الله عليه وسلم went out and said: 'We have work to do; whoever has a mount ready should mount it and come with us.' Some people asked permission, saying, 'Our mounts are in the elevated areas of Medina; shall we bring them from there?' The Prophet صلى الله عليه وسلم said: 'No, only those whose mounts are currently present should come.' Thus, the Prophet صلى الله عليه وسلم and his companions رضي الله عنهم set out until the Prophet صلى الله عليه وسلم reached Badr before the polytheists. Then the polytheists also arrived. The Prophet صلى الله عليه وسلم said: 'None of you should advance towards anything, and in battle, do not go ahead of me.' Then the polytheists approached. The Prophet صلى الله عليه وسلم said: 'My companions! Stand ready for the Paradise whose width is equal to the earth and the heavens.' Anas رضي الله عنه says that Umair bin Hamam Al-Ansari رضي الله عنه said: 'O Messenger of Allah! Is the width of Paradise equal to the earth and the heavens?' The Prophet صلى الله عليه وسلم said: 'Yes.' He (Umair رضي الله عنه) said: 'Wow, wow.' The Messenger of Allah صلى الله عليه وسلم said: 'What made you say "wow, wow"?' He said: 'Nothing, O Messenger of Allah! I only said it hoping that I might be among the people of Paradise.' The Messenger of Allah صلى الله عليه وسلم said: 'Then you are among the people of Paradise.' Anas رضي الله عنه says that then he (Umair رضي الله عنه) took out some dates from his quiver and began to eat them, then said: 'If I live until I finish eating these dates, then this life will be very long.' Anas رضي الله عنه says that he threw those dates away and then fought the polytheists until he was martyred."
Reference: (Sahih Bukhari and Muslim) (Narrated by Muslim, Book of Leadership, Chapter on Affirmation of Paradise for the Martyr, Number: 1901)
Derived Benefits
➊ Spying to keep an eye on the enemy's conditions is permissible.
➋ If the leader conceals the matter of the battle so that news of the fight does not spread and no harm occurs, this is also permissible and even preferable and better.
➌ During the battle, entering the enemy's ranks for martyrdom is also permissible.
➍ In war, the orders given by the leader should be obeyed.
➎ Justification for inspiring the desire for martyrdom: From the mentioned hadith, the leader of the army gets the justification to inspire his companions with the desire for martyrdom.
