Spurgeon uses this passage to explain to us a precious truth.
"Jehoiachin wasn't sent away from the kings' palace with provisions that would last him for months; rather, his allowance was given to him on a daily basis. In this he very much depicts the happy position of all the Lord's people. A daily portion is all that a person really wants. We don't need tomorrow's supplies; that day has not yet dawned, and its wants are as yet unborn. The thirst which we may allow in the month of June doesn't need to be quenched in February, for we don't feel it yet; if we have enough for each day as the days arrive we shall never know want. Sufficient for the day is all that we can enjoy.
We cannot eat or drink or wear more than the day's supply of food and clothing; the surplus gives us the care of storing it, and the anxiety of watching against a thief. One staff aids a traveler, but a bundle of staves is a heavy burden. Enough is not only as good as a feast, but is all that the complete glutton can truly enjoy. This is all that we should expect; a craving for more than this is ungrateful.
When our Father doesn't give us more, we should be content with His daily allowance. Jehoiachin's situation is ours; we have a sure portion, a portion given to us by the king, a gracious portion, and a perpetual portion. Here, surely, is grounds for thankfulness.
Dear Christian reader, in matters of grace you need a daily supply. You have no store of strength. Day by day you must seek help from above. It is a very sweet assurance that a daily portion is provided for you. In the world, through the ministry, by meditation, in prayer, and waiting upon God you shall receive renewed strength. In Jesus all necessary things are laid up for you. So, then, enjoy your continual allowance. Never go hungry while the daily bread of grace is on the table of mercy."
Morning and Evening by Spurgeon - page 90