Every man shall receive his own reward according to his own labor.
Each of us is responsible to the Lord for how we serve Him. He has some part for us to fill in service in His vineyard. One of the great comforts that we can get from Scripture is that the Lord keeps a record of what we do for Him and He will reward us in a coming day. It doesn’t matter that no one else knows what we have done. If, in our labor, we are hidden and Christ is glorified, then there will be reward. And the reward is for what we have done - not what someone else did.