Brian McLaren was asked the question, What is the Gospel? Here is his response...
“I think this is where it gets interesting because one of the ways that what we do becomes colonization, when we’re going to represent a religion and trying to make converts to a religion… but the good news isn’t the good news of Christianity, it’s the good news of the Kingdom of God. And I think that Fatmire [Muslim peace activist also present at conference and sitting next to him on the panel] working for peace, is an agent for peace, and I’d much rather her be working for peace being who she is than… becoming a person in a church worrying about the list over there on that wall. [on “the list” are things non-essentials like speaking in tongues, etc.)
So, to me there’s something we really have to grapple with about whether the border of a religion is the border of the kingdom of God. And I think that’s a question we’d be wise to raise. I liked what you said about there not being despair when you’re among the extremely needy people. Wouldn’t it be interesting if we found out that God is present wherever there’s suffering because God is there bringing healing and God is really present wherever people are working against injustice because that’s the work of God, wherever people are working for peace. And then the we find that the place that God isn’t is where you have a bunch of affluent people who are self-absorbed… and that wouldn’t surprise me why they would get depressed, because, in some way, it’s not that God isn’t present but they’re snoring through the presence of God.”
First off how do you respond to the question What is the Gospel by jumping immediately to colonization, that betrays a great deal about where he's at.
Second, how can the Good News not be the Good News of Christianity. When Jesus was asked the question how can one know the way He responded in this way.
John 14:6-7 - Jesus said to him, "I am the way, and the truth, and the life. No one comes to the Father except through me.  If you had known me, you would have known my Father also. From now on you do know him and have seen him."
When Jesus was giving His disciples their last command before His ascension, He did not command that we all become peace activists, He commanded that we, "Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,  teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age." (Matt 28:19-20)
I am not denying that we have a calling to help the poor, but our primary calling is to share the Good News of Jesus substitutionary death, His death that brings us forgiveness, and reconciliation with the Father. How can any news compare with this, how can any calling compare with the privilege of sharing the news that will spare people eternal torment and grant them eternal life in the presence of God.
McLaren appears to be fleeing the shame of conversionist Christianity, let us embrace the conversionist Christianity of our Savior, and lets close with His words.
"Truly, truly, I say to you, unless one is born again he cannot see the kingdom of God."