There was a measurement of manna that everyone was supposed to collect, as it states (16:16)... "An omer for each person, according to the number of persons... in his tent..." If there were five people in one's family, then he should gather and bring home five omers – an omer per head.
The next pasuk (16:17) states, ... "Bnei Yisrael did so: They gathered, both the one who gathered much and the one who gathered little." Rashi explains, "Some gathered too much manna, and some gathered too little, but when they came home, they measured... and they found that the one who had gathered too much had not exceeded an omer for each person who was in his tent, and the one who had gathered too little also had an omer per person. This was a great miracle that occurred with the manna."
We learn from this episode three essential lessons related to the pursuit of parnassah and rules of hishtadlus and bitachon:
- Everyone must make hishtadlus. As it states (Bereishis 3:19)... "With the sweat of your brow you shall eat bread." And it states (Tehillim 104:23)... "Man goes out to his work, to his labor until evening."
- Some people didn't make sufficient hishtadlus. They were obligated to collect an omer per head, but they collected less. Even so, they didn't lose manna because of that. When they came home and measured the amount of manna that they had, they found a manna per head. They discovered that the hishtadlus isn't the root of their parnassah, and each person receives what is destined for him.
- It states (16:18)... "They measured with an omer, and whoever gathered much did not have more..." This taught the nation that doing extra hishtadlus won't result in having more.
