Abu Musa reported God’s Messenger as saying, “The gates of paradise are under the shadow of the swords.” A man with a ragged appearance got up and asked Abu Musa whether he had heard God's Messenger say that; and when he received the reply that he had, he returned to his companions, said, “I salute you,” then broke the scabbard of his sword and threw it away, then went towards the enemy with his sword and plied it till he was killed.
Abu Sa'id reported God’s Messenger as saying, “If anyone is pleased with God as Lord, with Islam as religion and with Muhammad as Messenger, paradise will be assured to him.” Abu Sa'id was delighted with this and asked him to repeat it. He did so and then said, “There is also something else for which God will raise a servant in paradise a hundred degrees between each two of which there is a distance like that between heaven and earth.” He asked God's Messenger what it was and he replied, “jihad in God's path; jihad in God’s path; jihad in God’s path.”
Ibn ‘Abbas reported God’s Messenger as saying to his companions, “When your brethren were smitten at the battle of Uhud God put their spirits in the crops of green birds which go down to the rivers of paradise, eat its fruits and nestle in lamps of gold in the shade of the Throne. Then when they experienced the sweetness of their food, drink and rest they asked who would tell their brethren about them that they were alive in paradise in order that they might not cease to desire paradise or recoil in war. God most high said He would tell them about them, so He sent down, ‘And do not consider those who have been killed in God’s path to be dead; nay, they are alive in the presence of their Lord and are being supplied with provision . ..” (Al-Qur’an; 3:169 ff.)
‘Ubada b. as-Samit reported God’s Messenger as saying, “He who fights in God’s path with no intention but getting a tethering rope will have what he intended.”*
* This saying advocates the necessity of having proper motives. If all one wants is some material gain that is all he will get, for he will not deserve any eternal reward.