John 18:15 Simon Peter followed Jesus, and so did another disciple. Since that disciple was known to the high priest, he entered with Jesus into the courtyard of the high priest, 16 but Peter stood outside at the door. So the other disciple, who was known to the high priest, went out and spoke to the servant girl who kept watch at the door, and brought Peter in. 17 The servant girl at the door said to Peter, “You also are not one of this man’s disciples, are you?” He said, “I am not.” 18 Now the servants and officers had made a charcoal fire, because it was cold, and they were standing and warming themselves. Peter also was with them, standing and warming himself. ESV
What is the general theme of the passage?
Peter and another disciple are literally following Jesus as he’s taken to yet another place of judgement about his identity. Out of deference to the identity of the other disciple, who is apparently known as a follower of Jesus, the door has been opened to Peter. He’s been brought into this place where his identity is unknown, and his response to a simple question, “ I am not,” reveals he doesn’t know himself yet either.
What does it say about God (or Jesus or the Holy Spirit?)
There is power in everything that is implied in this verses. Peter thinks he’s followed Jesus here, but he’s been led to this place. He could have been left outside the door, but he’s been brought in. The Lord has a purpose for the simple question from a curious girl; to begin to reveal Peter’s identity to himself through a misspoken answer.
What does it say about people?
The strength of those who “purpose” to follow Jesus is not their innocence. It’s their willingness to face Jesus with their imperfection knowing He will forgive because He has given them their purpose…and His love is the perfection they need. 
Is there truth here for me?
I actually felt a physical twinge in my chest as I read Peter’s response to that servant girl. My heart made some connection between the odd exchange in John 13 at that special dinner where Peter asked John to ask Jesus who was going to betray Him. It’s always seemed odd to me he needed to ask what they were all wondering. Peter wasn’t the only one that needed reassurance of his innocence that night but now in this place he’s heard his own misspoken words of denial, “I am not.” It may not have happened right then but surely those three words became his own twinge of guilt…as he remembered that night and realized he wasn’t innocent after all…he was a betrayer!
Peter’s misspoken words, “I am not,” have pierced my heart. I felt those words because I’ve heard my own. I’ve realized it’s easy to excuse misspoken words as something other than betrayal and then accept my misplaced relief as the standard of my innocence. I would like to be innocent but innocence was lost thousands of years ago. Instead Jesus has agreed to the truth of my purpose to follow him and offered to take my misspoken words and misplaced relief as an act of repentance and make them into something more purposeful than innocence…purity.
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