Commentaries:
So, my son, be strong in the grace that Christ Jesus gives. Everything that you have heard me teach in public you should in turn entrust to reliable men, who will be able to pass it on to others. Put up with your share of hardship as a loyal soldier in Christ's army. Remember: 1. That no soldier on active service gets himself entangled in business, or he will not please his commanding officer. (Phillips)
He shows us that a soldier's primary responsibility is to please the one who enlisted him in this service. He makes it clear that our primary responsibility, our loyalty, is to Jesus Christ—not a corporation, not even to an apostle of that corporation. Christ is the one who enlisted us. The man was merely used.
He goes on to say that a soldier must be single-minded. If he is not single-minded and gets himself involved in things other than carrying out the commands of his officer, then he will not be trustworthy. He will not be willing to endure hardship and put up with his share of suffering. He will not endure if he is deeply entangled in civilian pursuits or distracted by other concerns.
John W. Ritenbaugh
Endure as a Good Soldier
Does that not picture someone who is striving to finish at the top, striving to win, to be the best that he possibly can? He does not desire to be just an "also ran," one of the pack, but to be somebody whom God looks upon as worth watching.
We have to put this in relation to what God wants us to be. Does He not want us to glorify Him by being as much like Him and Jesus Christ as possible? That is what real mastery is! Within the context, mastery is to be like Christ.
John W. Ritenbaugh
The Covenants, Grace, and Law (Part Twenty-Two)
Other Forerunner Commentary entries containing 2 Timothy 2:4:
1 Corinthians 5:12-13
1 Corinthians 9:24-27
1 Corinthians 15:26
2 Peter 3:9