Now therefore perform the doing of it; that as there was a readiness to will, so there may be a performance also out of that which ye have.

Now therefore perform ye it also in deed; that as your mind is forward to be willing, so it may be also to perform, out of that which you have.

Now therefore finish the doing of it; that as there was a readiness to will, so there may be a performance also out of that which ye have.

and now also finish doing it, that even as there is the readiness of the will, so also the finishing, out of that which ye have,

And now complete the doing also, in order that, just as there was then the eagerness in desiring, there may now be the accomplishment in proportion to your means.

Then make the doing of it complete; so that as you had a ready mind, you may give effect to it as you are able.

So, truly now, accomplish this in deed, so that, in the same manner as your willing mind is prompted, you may also act, out of that which you have.

And now I want you to complete the work, so that its completion may correspond with your willing readiness – in proportion, of course, to your means.

Now what ye have begun to do. It is probable, that the ardor of the Corinthians had quickly cooled down: otherwise they would, without any delay, have prosecuted their purpose. The Apostle, however, as though no fault had as yet been committed, gently admonishes them to complete, what had been well begun. When he adds -- from what you have, he anticipates an objection; for the flesh is always ingenious in finding out subterfuges. Some plead that they have families, which it were inhuman to neglect; others, on the ground that they cannot give much, make use of this as a pretext for entire exemption. Could I give so small a sum? All excuses of this nature Paul removes, when he commands every one to contribute according to the measure of his ability. He adds, also, the reason: that God looks to the heart -- not to what is given, for when he says, that readiness of mind is acceptable to God, according to the individual's ability, his meaning is this -- "If from slender resources you present some small sum, your disposition is not less esteemed in the sight of God, than in the case of a rich man's giving a large sum from his abundance. (Mark 12:44.) For the disposition is not estimated according to what you have not, that is, God does by no means require of thee, that thou coldest contribute more than thy resources allow." In this way none are excused; for the rich, on the one hand, owe to God a larger offering, and the poor, on the other hand, ought not to be ashamed of their slender resources.

As there was a readiness to will - Now accomplish the thing, and be not satisfied with having begun it. Do not suppose that the intention was sufficient, or that you are now released from the obligation. A year indeed has elapsed; but the necessity of the aid for the poor has not ceased. The sentiment here is, that if we have felt it our duty to aid in a cause of benevolence, and have commenced it, and have then been interrupted in executing our purpose, we should seize the first favorable opportunity to accomplish what we had designed. We should not regard ourselves as released from our obligation, but should, from a regard to consistency and our obligation to God, accomplish what we had intended.
Out of that which ye have - According to your ability; see 2-Corinthians 8:12. It should be in proportion to your means.

A readiness to will, so there may be a performance - Ye have willed and purposed this; now perform it.
Out of that which ye have - Give as God has enabled you; and give as God has disposed you. He requires each man to do as he can; and accepts the will where the means are wanting to perform the deed.

Now therefore perform the doing of it,.... This is a conclusion from the former advice, to finish what was readily willed; for as it is not enough to do a thing, unless it is done cheerfully and willingly, so it is not sufficient to express a good will to such service as is here called to, without doing it; both should go together:
that as there was a readiness to will, so there may be a performance also; in some cases there is neither power nor will to do good; in others there is will, when there is not a power; but in this case of beneficence to the poor saints, as there was a willingness declared, there was an ability in the Corinthians to perform; they had it in the power of their hands, more or less, to act: and the apostle in the last clause of this verse points out the rule and measure of their liberality,
out of that which you have; according to your abilities, and as God has prospered you; and with which he shuts up the mouths of all objectors, rich and poor: should the rich say, would you have us give away all we have? the answer is, no; but "out of that which you have", something of it, according as you are able; should the poorer sort say, we are in mean circumstances, we have families to provide for, and can spare little, and what we can do is so trifling, that it is not worth giving or accepting; the reply is, give "out of that which you have", be it less or more; it follows,

perform--"complete the doing also" (see on 2-Corinthians 8:10).
a readiness to will--Greek, "the readiness of will"; referring to 2-Corinthians 8:10, where the Greek for "to be forward," ought to be translated as here, "to will."
performance--"completion" [ALFORD], The godly should show the same zeal to finish, as well as to begin well, which the worldly exhibit in their undertakings (Jeremiah 44:25).