Bless your felllow Jews and you'll be blessed. What does that mean? When you see a man in the street who looks like a frum Jew, you don't have to go over to him. As you pass across the street, say, " Hashem should give that man success in parnassa! He should have nachas from his children! He should live long!"
It cost you money? It doesn't cost you a penny. And it's such a good investment that you are promised a bracha. It seems so wild, it seems so insane, to lose that opportunity, to bless your fellow Jew. -- Ten Easy Ways to Gain Real Wealth (#93)