'Toiled' in the Bible

Yet when I considered all the effort which I expended and the toil with which I toiled to do, then behold, "Everything [is] vanity and chasing wind! There is nothing profitable under the sun!"

So I hated all my toil with which I have toiled under the sun, for I must leave it behind to someone who will be after me.

And who knows [whether] he will be wise or foolish? Yet he will exercise control of all [the fruit of] my toil with which I toiled wisely under the sun. This also [is] vanity!

So {I began to despair} of all the toil with which I toiled under the sun.

For although a person may toil with great wisdom and skill, he must leave his reward to someone who has not toiled for it. This also [is] vanity and a great calamity.