Your attitude should be the same as that of Christ Jesus...

"The point Paul is making, then, is that we have been called not only to enjoy the comforts of the gospel but also to pass them on. If you have received personal benefit from the gospel at the hands of other believers, then maintain the tradition: treat others in such a way that they too will receive benefit. After all, we profess to trust and follow one whose entire mission was characterized by self-denial: in obedience to his heavenly Father he gave and gave and gave. Your attitude, writes Paul, should be the same as his: give and give and give.

Do we not sometimes say as much to our young people? They go through self-conscious phases in which they think that everyone is staring at them and that no one likes them. They fall into a pattern of self-pity in this regard, sooner or later we say to them, "Look, stop your whining. To whom have you shown yourself a friend? Those who would have friends must show themselves friendly. Have you looked around your classroom and found the students who are loneliest, most commonly rejected, alone, and tried to befriend them? Why not? Why do you think everyone should be friendly to you when you make no effort to befriend others?"

Of course, all such arguments (as useful as they are) are narrowly pragmatic. Paul's argument is far stronger. We owe love and encouragement to others because we have received so much. Above all, we owe this kind of character and stance to others because we profess to follow Christ Jesus, and that, supremely,  is his character and stance. It is always deeply disturbing to find some professed Christians, members of the church, who think only of what they get. What a pathetically Christ-denying attitude! Give and give and give. We are called not only to enjoy the comforts of the gospel but also to pass them on."

D.A. Carson

Basics for Believers

p 60-61