1 Corinthians 15:10
But what I am I am by the grace of God, and His grace bestowed upon me did not prove ineffectual. But I labored more strenuously than all the rest--yet it was not I, but God's grace working with me.
1 Corinthians 15:58
Therefore, my dear brethren, be firm, unmovable, busily occupied at all times in the Lord's work, knowing that your toil is not fruitless in the Lord.
Galatians 6:9
Let us not abate our courage in doing what is right; for in due time we shall reap a reward, if we do not faint.
Colossians 1:29
To this end, like an earnest wrestler, I exert all my strength in reliance upon the power of Him who is mightily at work within me.