I know that there is no good in them, but for a man to rejoice, and to do good in his life.

And I have known that there was no better thing than to rejoice, and to do well in this life.

I know that there is nothing good for them but to rejoice and to do well in their life;

I have known that there is no good for them except to rejoice and to do good during their life,

I am certain that there is nothing better for a man than to be glad, and to do good while life is in him.

I know that there is nothing better for them, than to rejoice, and to get pleasure so long as they live.

And I realize that there is nothing better than to rejoice, and to do well in this life.

In them - i. e., in the sons of men.
To do good - In a moral sense. Physical enjoyment is referred to in Ecclesiastes 3:13.

I know that there is no good in them, but, etc. - Since God has so disposed the affairs of this world, that the great events of providence cannot be accelerated or retarded by human cares and anxieties, submit to God; make a proper use of what he has given: do thyself no harm, and endeavor as much as possible to do others good.
Enjoy, and bless thyself; let others share
The transient blessing: 'tis the gift of God.

I know that there is no good in them,.... In these things; as the Arabic version; in the creatures, as Jarchi; in all sublunary enjoyments; in everything the wise man had made a trial of before, as natural Wisdom and knowledge, worldly pleasure, riches, and wealth; the "summun bonum", or happiness of men, did not lie in these things; this he knew by experience, and had the strongest assurance of it: or in them, that is, the children of men, as the Targum: there is no real good thing in them, nor comes out of them, nor is done by them; they cannot think a good thought, nor do a good action, of themselves. Or rather the sense is, I know there is nothing better for them than what follows:
but for a man to rejoice; not in sin and sinful pleasures, in a riotous, voluptuous, and epicurean manner; but to be cheerful, and enjoy the blessings of life in a comfortable way, and with a thankful heart; and especially to rejoice in spiritual things, and above all in Christ; and not in any self-boastings or carnal confidences, all such rejoicing is evil; see Ecclesiastes 9:7. The Targum is,
"but that they rejoice in the joy of the law;''
but it is much better to rejoice in the things of the Gospel, which is indeed a joyful sound;
and to do good in his life: to himself and family, by making use of the good things of life, and not withholding and hoarding them up; and to others, to all men, as opportunity offers, and especially to the household of faith; and not only by liberality and alms deeds, but by doing all good works, from right principles and to right ends, and that always, as long as he lives, Galatians 6:9.

in them--in God's works (Ecclesiastes 3:11), as far as relates to man's duty. Man cannot fully comprehend them, but he ought joyfully to receive ("rejoice in") God's gifts, and "do good" with them to himself and to others. This is never out of season (Galatians 6:9-10). Not sensual joy and self-indulgence (Philippians 4:4; James 4:16-17).

"Thus I then perceived that among them (men) there is nothing better than to enjoy themselves, and indulge themselves in their life." The resignation would acquire a reality if לע טוב meant "to do good," i.e., right (lxx, Targ., Syr., Jeremiah., Venet.); and this appears of necessity to be its meaning according to Ecclesiastes 7:20. But, with right, Ginsburg remarks that nowhere else - neither at Ecclesiastes 2:24, nor Ecclesiastes 3:22; Ecclesiastes 5:17; Ecclesiastes 8:15; Ecclesiastes 9:7 - is this moral rendering given to the ultimatum; also טוב ור, 13a, presupposes for לע טוב a eudemonistic sense. On the other hand, Zckler is right in saying that for the meaning of עשות תוב, in the sense of "to be of good cheer" (Luth.), there is no example. Zirkel compares εὖ πράττειν, and regards it as a Graecism. But it either stands ellipt. for לע לו טוב (= להיטיב לו), or, with Grtz, we have to read טוב לראות; in any case, an ethical signification is here excluded by the nearest connection, as well as by the parallels; it is not contrary to the view of Koheleth, but this is not the place to express it. Bam is to be understood after baadam, Ecclesiastes 2:24. The plur., comprehending men, here, as at Ecclesiastes 3:11, wholly passes over into the individualizing sing.
But this enjoyment of life also, Koheleth continues, this advisedly the best portion in the limited and restrained condition of man, is placed beyond his control: -

Them - In creatures or worldly enjoyments. To do good - To employ them in acts of charity and liberality.