John Calvin Commentary Isaiah 62:9

"but they that have garnered it shall eat it, and praise Jehovah; and they that have gathered it shall drink it in the courts of my sanctuary." — Isaiah 62:9 (ASV)

For they who have gathered it shall eat it. This is an explanation and confirmation of the preceding statement. For, after having testified that He will no longer allow what the Church possesses to be exposed as plunder, He adds that she will enjoy her possessions.

Yet He shows that “corn and wine” are justly called our own when we have obtained them by honest industry. For those who violently seize the bread of others, or obtain it by unlawful means, do not have it from the Lord, and cannot attribute it to His blessing, as if they possessed it lawfully. To this corresponds what is said in the Psalm:

You shall eat the labor of your hands; you shall be happy, and it shall be well with you (Psalms 128:2).

And shall praise Jehovah. But when He promises that those who cultivate the soil will have food, why does He say that they will give thanks to God? And why do people praise God, if by their own labor they gather the corn and procure the wine? It appears to be only a pretended thanksgiving if these things are ascribed to the toil and industry of humans, and God deserves no praise if people procure food by their own labor.

But it should be observed that the Prophet, after having shown what is the lawful method of seeking food, at the same time adds that our labor will be fruitless if the Lord does not supply us with food. For all that we have belongs to God, and to Him alone all that we obtain ought to be ascribed.

Shall drink wine in my holy courts. He alludes to the solemn act of offering sacrifices, for they could drink in other places, and everyone could eat in their own dwelling.

But the allusion is to that ceremony which was observed in consecration, when the law required that the first-fruits should be an offering (Leviticus 2:12, Leviticus 23:10), so that the produce of the year might be dedicated to God. In the writings of Moses we frequently encounter these words:

You shall feast and rejoice in the presence of your God (Deuteronomy 12:18).