Exodus 16 – They were to live by faithfulness and obedience, not by how they felt. 2017

Exo 16:16
"This is what the LORD has commanded, 'Gather of it every man as much as he should eat; you shall take an omer apiece according to the number of persons each of you has in his tent.'"

An omer is a little over two quarts. This is plenty of food and nourishment for a person every day. They were not to gather more of it than an omer for each person.

Exo 16:17
And the sons of Israel did so, and some gathered much and some little.

Exo 16:18
When they measured it with an omer, he who had gathered much had no excess, and he who had gathered little had no lack; every man gathered as much as he should eat.

Some people gathered more than an omer, some gathered less. But when they got together, they all measured it with an omer and shared it with one another so they all had the prescribed amount.

Exo 16:19
And Moses said to them, "Let no man leave any of it until morning."

Exo 16:20
But they did not listen to Moses, and some left part of it until morning, and it bred worms and became foul; and Moses was angry with them.

This spoiling of the food was not a totally natural phenomenon. Elohim used this spoiling process to punish the disobedient. They were to live by faithfulness and obedience to Elohim and not by how they felt or by their own desires.