Musannaf Ibn Abi Shaybah

Hazrat Yazid bin Shajrah, may Allah have mercy on him, says that swords are the keys to Paradise. When a person advances towards the enemy, the angels say, "O Allah! Help him." If he retreats, the angels say, "O Allah! Forgive him." With the very first drop of blood that falls from the wound caused by the sword, all his sins are forgiven. Two houris descend from Paradise for him and say, "We are for you." He says to both of them, "I am for you."