1 Thessalonians 2:1
For you brothers [should] know that our coming to you was not a waste of time.
1 Corinthians 15:2
[and] you have been saved by it also, if you hold on to it firmly [i.e., continue believing and practicing it]. For if you do not [hold on to it firmly], you will have believed [it] all for nothing.
1 Corinthians 15:10
But I am whatever I am because of God's unearned favor, and the favor He showed me was not for nothing [i.e., Paul made the most of his conversion by being extra diligent in his service to God]. But I worked harder than all the other apostles, yet it was not I, but God's favor on me [that accomplished it].
1 Corinthians 15:58
Therefore, my dearly loved brothers, stand firm [in the faith]; do not be moved [from your commitment]. Always do your best to work for the Lord, since you know that your labor in the Lord's [service] is not for nothing.
2 Corinthians 6:1
As workers together with God we urge you also, who have received God's unearned favor, do not allow it to be for nothing,
Galatians 2:2
[It was] in response to [a divine] revelation that I went [there] and explained to them [I. e., the apostles and elders] the Gospel [message] that I had been preaching among the Gentiles. Then [later on I presented it] privately before those who were highly regarded [i.e., the three apostles, verse 9] so [they would have verification that] my running [i.e., ministry] had not been, nor was now, in vain.
Galatians 4:11
I am afraid for you, [i.e., for your spiritual safety], that possibly I may have spent a lot of effort on your behalf for nothing.
Philippians 2:16
as you hold out [i.e., offer to people] the message of [never ending] life. Then I will have something to boast about on the day of Christ's [return, See 1:6], that I had not run the race for nothing nor had worked for nothing.
1 Thessalonians 1:3-10
We continually remember, in the presence of our God and Father, the work produced by your faith, the labor prompted by your love, and your endurance motivated by your hope in our Lord Jesus Christ.
1 Thessalonians 2:13
And because of this we also thank God continually that, when you people received the message of God, which you heard from us, you did not accept it as a message from [mere] human beings, but as it truly is, the message from God, which is at work in you believers.
1 Thessalonians 3:5
[So], for this reason, when I could not stand it any longer, I also sent [Timothy] to find out about your faith. I was afraid that somehow the tempter [i.e., Satan] had tempted you [to give up] and that our work [on your behalf] will have become useless.
2 Thessalonians 1:10
On that day Jesus will return to be honored by His saints [i.e., God's holy people] and to be marveled at [i.e., in reverence] by all those who had believed [in Him]. [This will happen] because you have believed our testimony to you [about Christ].
2 Thessalonians 3:1
Finally, brothers, pray for us, so that the Lord's message will spread quickly and be honored [by people], even as it was among you.