Every Yid must believe with everything he does: parnassah, his other worldly deeds, and also in regards to spirituality and avodas Hashem, that the idea that came to his mind regarding what he should do was sent to him from Heaven to direct him in the right path, so he should earn money in his financial endeavors, because Hashem wanted, at that time, that he should earn money.

Or, chas veshalom the opposite, when Hashem wants him to lose money, Hashem places into his heart a thought to do such and such, and thereby he loses money. ~ The Meor Einayim