who is the church?

So I've been pondering the message given in church this morning. What first got my attention was when the pastor, who happened to be a guest, stood up and said "I have prepared a message to deliver to you today, but if these are simply my words then you will leave and be the exact same as you were when you entered those doors. but if God speaks His words through me, you will be changed and never be the same." He proceeded to pray and gave the message. I was listening intently on the message he spoke concerning those who are held in slavery, those forced to work as prostitutes, and about the rights taken from orphans and widows. He went on to tell the story of a young girl who was held captive for years in a brothel where she was forced to service 4-5 men daily. Yet on the wall of her tiny room she had posted these words from Psalm 27- "The LORD is my light and my salvation whom shall I fear? The LORD is the stronghold of my life-of whom shall I be afraid? When evil men advance against me to devour my flesh, when my enemies and my foes attack me, they will stumble and fall. Though an army besiege me, my heart will not fear; though war break out against me, even then will I be confident. " If a young girl can claim this as her hope despite unthinkable circumstances- it shames me to consider my lack of confidence at times. The pastor went on to assert that God has given us a solution to many of these tragic situations, the church. In other words, us. I got to thinking, who exactly is "the church?" I mean its easy to hear sermons like this and think "someone else will pray for her" or "someone else will donate money to their cause" or "someone else will go on that mission trip," because after all the church is made up of a body of believers right? We often assume there are others who will take on the responsibility of being the church to non-believers. It is a dangerous choice to become comfortable because God clearly states in Isaiah 1:17 that we are required to seek justice, to encourage the oppressed, defend the cause of the fatherless, and plead the case of the widow. God does not give exemptions or exceptions as to who He wants to be "the church" to the oppressed. In fact to the contrary in Romans God specifically says we all have different gifts, some have the gift of serving or teaching, others encourage, show mercy, or lead us. It is up to us as the body to show the world that God is good. It isn't simply up to he or she sitting in the seats next to me- how will I respond to God's call for justice? I am not an observer or merely a spectator, I am the church. It's up to me how I will carry out that responsibility.