The Prophet ﷺ said: Fighting is of two kinds: The one who seeks Allah's favour, obeys the leader, gives the property he values, treats his associates gently and avoids doing mischief, will have the reward for all the time whether he is asleep or awake; but the one who fights in a boasting spirit, for the sake of display and to gain a reputation, who disobeys the leader and does mischief in the earth will not return credit or without blame.  

عَنْ رَسُولِ اللَّهِ ﷺ أَنَّهُ قَالَ الْغَزْوُ غَزْوَانِ فَأَمَّا مَنِ ابْتَغَى وَجْهَ اللَّهِ وَأَطَاعَ الإِمَامَ وَأَنْفَقَ الْكَرِيمَةَ وَيَاسَرَ الشَّرِيكَ وَاجْتَنَبَ الْفَسَادَ فَإِنَّ نَوْمَهُ وَنَبْهَهُ أَجْرٌ كُلُّهُ وَأَمَّا مَنْ غَزَا فَخْرًا وَرِيَاءً وَسُمْعَةً وَعَصَى الإِمَامَ وَأَفْسَدَ فِي الأَرْضِ فَإِنَّهُ لَمْ يَرْجِعْ بِالْكَفَافِ  

A man said: Messenger of Allah, a man wishes to take part in jihad in Allah's path desiring some worldly advantage? The Prophet ﷺ said: He will have not reward. The people thought it terrible, and they said to the man: Go back to the Messenger of Allah ﷺ, for you might not have made him understand well. He, therefore, (went and again) asked: Messenger of Allah, a man wishes to take part in jihad in Allah's path desiring some worldly advantage? He replied: There is no reward for him. They again said to the man: Return to the Messenger of Allah. He, therefore, said to him third time. He replied: There is no reward for him.  

يَا رَسُولَ اللَّهِ رَجُلٌ يُرِيدُ الْجِهَادَ فِي سَبِيلِ اللَّهِ وَهُوَ يَبْتَغِي عَرَضًا مِنْ عَرَضِ الدُّنْيَا فَقَالَ رَسُولُ اللَّهِ ﷺ لاَ أَجْرَ لَهُ فَأَعْظَمَ ذَلِكَ النَّاسُ وَقَالُوا لِلرَّجُلِ عُدْ لِرَسُولِ اللَّهِ ﷺ فَلَعَلَّكَ لَمْ تُفَهِّمْهُ فَقَالَ يَا رَسُولَ اللَّهِ رَجُلٌ يُرِيدُ الْجِهَادَ فِي سَبِيلِ اللَّهِ وَهُوَ يَبْتَغِي عَرَضًا مِنْ عَرَضِ الدُّنْيَا فَقَالَ لاَ أَجْرَ لَهُ فَقَالُوا لِلرَّجُلِ عُدْ لِرَسُولِ اللَّهِ ﷺ فَقَالَ لَهُ الثَّالِثَةَ فَقَالَ لَهُ لاَ أَجْرَ لَهُ