“And when the dew had gone up, there was on the face of the wilderness a fine, flake-like thing, fine as frost on the ground. When the people of Israel saw it, they said to one another, ‘What is it?’ For they did not know what it was. And Moses said to them, ‘It is the bread that the Lord has given you to eat'” (Exodus 16:14-15,ESV)
After the Lord had delivered them from the Egyptians by the mighty miracle of the parting of the Red Sea, the tribes of Israel journeyed on into the wilderness. There began to murmur and complain. They were not starving but they did have a need for sustenance. Of course there is a proper and respectful way to ask the Lord for relief but the Israelites felt that complaining was the best method. They discredited and mocked the faithfulness of the Lord and the authority of Moses. They looked fondly back to their slavery days and the fine food they supposedly had then. They forgot the slavery, bitterness, and pain of the old life.
The Lord graciously responded to their requests even though they were in the form of complaints. He gave them meat to eat, quail, an unexpected blessing. He also gave them total sustenance, however, in the form of manna. They would eat this manna for the next 40 years and it would meet their every need.
The Lord promises us to supply our every need for our life, physical as well as eternal. No thing or person in this life will provide such sustenance for God grants us it all by grace through faith in the person of Jesus. He alone is the Bread of Life. While the Lord tolerates and understands our complaints we need not grumble and whine to receive His grace and provision as the Israelites did. We need only ask with a humble and contrite heart and He will give us all that we need.