When we think of manna, we tend to think of daily provision, or the fact that manna was the Lord Jesus in a type. This is all good, but there is a good deal more. Recall also that when the manna was gathered, it was to be gathered for that day—sufficient unto the day is the grace thereof.
But there was one place where the manna would last, where it would not rot the same way it would in the tents of the Israelites. That place was inside the ark of the covenant, under the mercy seat. There, in that place, the bowl of manna was a bowl of mercy (Ex. 16:33). And it was not a small bowl either; it was not a small museum piece morsel, kept for sentimental reasons. God had them store up about 3/5 of a bushel within the ark of the covenant. His grace is sufficient.
God’s provision comes to you where you are, and the grace He provides is to be used by you as it comes. But never forget that there is a store of it, a plentiful store of it, inside the ark of the covenant. Never forget that God can keep what You need, and you cannot—even if you got it from God originally. In this life, grace comes on the fly and you may use it as it comes. But in your inheritance, grace is stored up, and it does not diminish.
When you pray on Tuesday afternoon for grace, that is your daily manna. Here, at this Table, we are at the mercy seat, and our provision does not and cannot fail. So come, and welcome, to Jesus Christ.
--From Doug Wilson's Blog & Mablog