Galatians 4:11
You make me fear that the labor which I have spent on you may have been wasted.
1 Thessalonians 3:5
Therefore, since I could no longer endure the uncertainty, I sent to make inquiries about your faith, fearing that the Tempter had tempted you, and that our toil might prove to have been in vain.
Galatians 2:2
It was in obedience to a revelation that I went; and I laid before the Apostles the Good News that I am proclaiming among the Gentiles. I did this privately before those who are thought highly of, for fear that I might possibly be taking, or might have already taken, a course which would prove useless.
Acts 16:6
They next went through the Phrygian district of Galatia, but were restrained by the Holy Spirit from delivering the Message in Roman Asia.
1 Corinthians 15:58
Therefore, my dear Brothers, stand firm, unshaken, always diligent in the Lord's work, for you know that, in union with him, your toil is not in vain.
2 Corinthians 11:2-3
I am jealous over you with the jealousy of God. For I betrothed you to one husband, that I might present you to the Christ a pure bride.
2 Corinthians 12:20-21
For I am afraid that perhaps, when I come, I may find that you are not what I want you to be, and, on the other hand, that you may find that I am what you do not want me to be. I am afraid that I may find quarreling, jealousy, ill-feeling, rivalry, slandering, back-biting, self-assertion, and disorder.
Galatians 4:20
But I could wish to be with you now and speak in a different tone, for I am perplexed about you.
Galatians 5:2-4
Understand that I, Paul, myself tell you that if you allow yourselves to be circumcised, Christ will avail you nothing.
Philippians 2:16
Offering to men the Message of Life; and then I shall be able at the Day of Christ to boast that I did not run my course for nothing, or toil for nothing.
2 John 1:8
Take care that you do not lose the fruit of all our work; rather, reap the benefit of it in full.