Our Scripture reading for today is 1 John 2:18-19.
Verse 19, "They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us."
The Apostle John speaks of the sad reality that not everyone attending church is a possessing, born-again Christian.  It could be they made a profession of faith, but it was nothing more than reciting a prayer like a parrot would say, "Polly want a cracker".  This individual has completely walked away from the things of God and this would include the church.  
I would like to challenge each and every one of us reading this devotional today with the inspired words of the Apostle Paul in 2 Corinthians 13:5, "Examine yourselves, whether ye be in the faith; prove your own selves. Know ye not your own selves, how that Jesus Christ is in you, except ye be reprobates?  Are you in the faith?  You were not born a Christian.  No one is born a Christian.  Can you point to a time in your life when you, by faith, recognized your sinful condition and turned to Jesus Christ for your salvation?  You may not know the exact date, but you know that you made a choice to follow Jesus Christ.  This is not meant to bring doubt, but it is meant to bring assurance and confidence that we are the children of God.