κενός

But by the grace of God I am what I am, and His grace to me was not in vain. No, I worked harder than all of them—yet not I, but the grace of God that was with me.

You yourselves know, brothers, that our visit to you was not in vain.

You spoke by the Holy Spirit through the mouth of Your servant, our father David:‘Why do the nations rageand the peoples plot in vain?

I went in response to a revelation and set before them the gospel that I preach among the Gentiles. But I spoke privately to those recognized as leaders, for fear that I was running or had already run in vain.

At harvest time, he sent a servant to the tenants to collect his share of the fruit of the vineyard. But the tenants beat the servant and sent him away empty-handed.