With many struggling in business at this time, people are asking what they could do spiritually to improve their financial status. We know the Sefer Hachinuch writes in mitzva 430 that whoever is careful to say Birkat Hamazon properly will have his sustenance given to him in a dignified manner for his entire life. The Sefer Ta'ameh Haminhagim u'Mekoreh Hadinim writes that saying Birkat Hamazon out loud with joy is a segula for wealth.
A rabbi from Yerushalayim related that this past year he has had a lot of struggles in parnasa and Baruch Hashem, his daughter got engaged, which meant a lot more expenses. His friend encouraged him to start eating bread every single day and utilize the wondrous segula of saying Birkat Hamazon. The rabbi told this friend that his diet only allowed him to eat bread one day a week on Shabbat. But the friend insisted that the segula has been tried and tested and told him to eat just the bare minimum necessary to say Birkat Hamazon on a daily basis. Later that day, the rabbi went to the Kotel to pray Arbit and there he saw a Hashgacha Peratit newsletter. On the first page was a writeup from Rabbi Pinchas Shafer about a man who was struggling with parnasa, who began saying Birkat Hamazon and saw amazing yeshuot. The rabbi was convinced and he and his rebbetzin both accepted upon themselves to start eating bread every single day.
The first thing the rabbi said was how much he enjoyed saying Birkat Hamazon and truly concentrating when thanking Hashem. Less than two weeks since they started, a wealthy friend of his came over to him one day and said, "I want to help with the upcoming wedding of your daughter. And then he handed him an envelope with 10,000 shekels inside. The rabbi became emotional, seeing how Hashem had just helped him in such an open way.
That Friday, he told all of his children of the recent developments and asked them to each begin saying Birkat Hamazon with kavana from a siddur. He also told them that we don't do mitzvot just for a segula and proceeded to tell them what a zechut it was to thank Hashem properly for all of His goodness and chesed, especially during the mitzvat aseh of Birkat Hamazon. That Shabbat, they were all inspired to say Birkat Hamazon the right way.
During that upcoming week, the rebbetzin who had been unemployed found an easy and pleasant job. The rabbi who learned during the day and had a job at night, seeing all of the Heavenly help with parnasa, decided to ask for a raise at his job. The very next day, he was told that the raise was approved.
Furthermore, one of his children needed a new pair of shoes and went to the store to buy them. When he picked out the shoes he wanted, the salesman said, "Those are free." He explained that someone returned them after wearing them for an hour. He told that customer they couldn't take them back after they were worn. And so the person said, "No problem, just give them to someone who needs them." He put a mark on the box and that was the pair that this boy picked out.
Another one of the rabbi's children needed a new suit, and he heard there was a sale at a popular store. The regular price of a suit is about a thousand shekels. On the outside of the store, it said some suits were as much as 50% off, but when he saw the selection, he did not like any of those suits. He took the suit he liked to the register, and there he was told that on that suit there were two sales and the price came out to only 360 shekels.
Those are the stories that happened to them in just the last two months. The rabbi said the greatest gift he got from all of this is a new appreciation for saying Birkat Hamazon and thanking Hashem in general.