'Labour' in the Bible

But since to live means a longer stay on earth, that implies more labour for me--and not unsuccessful labour; and which I am to choose I cannot tell.

Therefore, my dearly-loved friends, as I have always found you obedient, labour earnestly with fear and trembling--not merely as though I were present with you, but much more now since I am absent from you--labour earnestly, I say, to make sure of your own salvation.

Yet I deem it important to send Epaphroditus to you now--he is my brother and comrade both in labour and in arms, and is your messenger who has ministered to my needs.