Hadith Qudsi 33
33) Narrated Ibn 'Umar Prophet quoted his Lord saying:Whoever of My slaves comes out to fight in My way seeking My pleasure, I guarantee him that I will compensate his suffering with reward and booty (during his lifetime) and if he dies, I would forgive him, have mercy on him and let him enter Paradise.
(This Haditb is fairly sound and reported in Musnad Ahmad).
-------------------------------
A soldier who fights in the way of Allah will be best rewarded by Allah in this world as well as in the Hereafter.