“One argument can destroy a hundred livelihoods,” wrote the Shlah HaKodesh.  That is, hatred and strife can shut down the channels of heavenly blessings, which are the very source of our sustenance.  In Likuety Moharan, Rabbi Nachman [of Breslov] explains this idea:

“When a person is about to become angry, he should realize that at that very moment, heaven is sending him a blessing of money, and that the evil inclination is trying to destroy this blessing.” ~ R’ Yaakov Meir Shechter