John Gill Commentary 2 Timothy 2:3

"Suffer hardship with [me], as a good soldier of Christ Jesus." — 2 Timothy 2:3 (ASV)

You therefore endure hardness
"Or afflictions"; as in (2 Timothy 4:5) . The same word is used there as here, and properly signifies, "suffer evil"; and means the evil of afflictions, as persecutions of every kind, loss of name and goods, scourging, imprisonment, and death itself, for the sake of Christ and the Gospel:

as a good soldier of Jesus Christ .
Christ is the Captain of salvation, the Leader and Commander of the people, who are made a willing people in the day of his power; or when he raises his forces, and musters his armies, these are volunteers, who willingly enlist themselves into his service, and under his banners fight his battles; and such who manfully behave against sin, Satan, and the world, are his good soldiers; such are all true believers in Christ, and particularly the ministers of the word, whose ministry is a warfare, and who fight the good fight of faith; and besides the above enemies, which they have in common with other saints, have to do with teachers, who are wolves in sheep's clothing.