Abu Dawud Book 8, Hadith Number 2506.
Narated By AbuAyyub : AbuImran said: We went out on an expedition from Medina with the intention of (attacking) Constantinople. AbdurRahman ibn Khalid ibn al-Walid was the leader of the company. The Romans were just keeping their backs to the walls of the city. A man (suddenly) attacked the enemy.
Thereupon the people said: Stop! Stop! There is no god but Allah. He is putting himself into danger.
AbuAyyub said: This verse was revealed about us, the group of the Ansar (the Helpers). When Allah helped His Prophet (PBUH) and gave Islam dominance, we said (i.e. thought): Come on! Let us stay in our property and improve it.
Thereupon Allah, the Exalted, revealed, “And spend of your substance in the cause of Allah, and make not your hands contribute to (your destruction)”. To put oneself into danger means that we stay in our property and commit ourselves to its improvement, and abandon fighting (i.e. jihad).
AbuImran said: AbuAyyub continued to strive in the cause of Allah until he (died and) was buried in Constantinople.