Paul wrote to Timothy, a young church leader in Ephesus, about matters he expected Timothy to share with the faith communities Timothy led and served. Towards the beginning, and again at the end of his letter, Paul encourages Timothy to "fight the good fight of faith." (1.18 & 6.12) All of the instructions and advice inbetween tell us what that fight was for: community leaders, the vulnerable, the true teachings of the faith, church leaders, contentment, one's personal purpose from God, and deep relationships.
What's interesting about the word "fight" is that it is in the middle voice. That means it's not a simple action-- we don't just get up and start fighting. The middle voice indicates that the action of the verb relates to the subject in some way. Meaning, our good fight of faith is both internal and external, and there are things in ourselves that need to change in order for the faith to go forth. It also means that dedicating ourselves to "the good fight of faith" will have an effect on us!
Paul wrote that if Timothy put these matters before the fellowship of believers he would be "a good servant of Christ Jesus, nourished on the words of faith and of the sound teaching" that Timothy has followed. (4.6) So we continue to study and learn from the letter of 1 Timothy today, yearning to gain congregational wisdom about our faith and witness.