Definition of Christianity

Via Exploring our Matrix, I read this great post by Theo Geek, commenting on another blog post here that says:

I think you’re right to define and emphasize justification by faith alone in Christ alone as the heart of the Christian gospel. That is without doubt or equivocation the fountainhead of everything else, and you don’t get to the rest of the “good news” unless you start there. In other words, to tell someone that it’s not really important to focus on the atonement, but rather that you can be a Christian just by being a “follower of Jesus” and by “living like Jesus” is not Christianity. To be a Christian is to believe in Jesus, repenting of sins and trusting for salvation in his atoning, reconciling, justifying, substitutionary death on the cross.

Theo Geek responds:

A message "to do good works here and now in the social and political realms" strikes me as an extremely accurate description of the content of Jesus' public ministry as depicted in the gospels. The gospels present Jesus' ministry as a campaign over social issues, period. The social gospel is certainly well-founded in the biblical accounts of Jesus' ministry. So, according to the above writer, the Christian gospel is apparently "in serious danger" of being reduced to, well, the gospels. Dang, we surely can't allow that, can we? Apparently not, because as our above writer continues, that is "no gospel at all". Excuse me while I go and cut the four gospels out of my bible. One wonders why Christ bothered preaching "no gospel at all" in the course of his three year ministry...

For me, the most amusing quote in the above is: '[the idea] that you can be a Christian just by being a “follower of Jesus” and by “living like Jesus” is not Christianity.' Excuse me while I go cut the rest of my New Testament out of my bible...

I would just add this Jesus passage from the Gospel of Matthew:

²⁴Then Jesus told his disciples, “If any want to become my followers, let them deny themselves and take up their cross and follow me. (Matthew 16:24)

It would seem to me that these words of Jesus might serve as an adequate definition of Christianity. It isn't easy; but it is simple enough to understand.