Here are two character qualities that make you useful in His service. The first is having a genuine love for the Body of Christ as Timothy did. And the second is having a genuine love for God as Peter did. One reason Paul put Timothy into service was because of his love of people. And one reason Jesus put Peter into service was for his love of God.( I am using the verses below to make a point. Timothy also loved God and Peter also loved people.)
19 But I hope in the Lord Jesus to send Timothy to you shortly, so that I also may be encouraged when I learn of your condition. 20 For I have no one else of kindred spirit who will genuinely be concerned for your welfare. 21 For they all seek after their own interests, not those of Christ Jesus.
16 He *said to him again a second time, “Simon, son of John, do you love Me?” He *said to Him, “Yes, Lord; You know that I love You.” He *said to him, “Shepherd My sheep.” 17 He *said to him the third time, “Simon, son of John, do you love Me?” Peter was grieved because He said to him the third time, “Do you love Me?” And he said to Him, “Lord, You know all things; You know that I love You.” Jesus *said to him, “Tend My sheep.
To sum up Love God and love people and you too may be given something to do for God.
Scripture quotations taken from the "NASB" (www.lockman.org )