This is another topic that has obviously been either confused or muddled.  Having no creed but the Bible alone, we look to the Bible to determine our terms of membership.  As a result, we do not "vote" a person into the congregation.  Neither do we have a probationary period, a special class, or any other such thing to become a member.  These things are simply not mentioned or even implied in scripture.

Terms of membership into the Lord's church are the same as those  for Salvation.  Ephesians 1:1-14 tells us that God has blessed those "In Him" or "In Christ" with every spiritual blessing, with redemption and forgiveness of sins, with an inheritance of Heaven, and with the Holy Spirit.  The 2nd chapter of Ephesians tells how all Christians, whether they were a Jew or Gentile (non-Jew) have been brought together in Christ.  This happened at the moment one was saved.  "For by grace you have been saved through faith, and that not of yourselves, it is the gift of God"  (Ephesians 2:8).  God's part was extending his grace (undeserved mercy), our part is faith.  The passage concludes:  "So then you are no longer strangers and aliens, but you are fellow citizens with the saints, God's household..."  (Ephesians 2:19). 

So then, when one is saved, he becomes part of God's household.  This example is clearly seen in Acts 2:37-41.  The people heard the message, repented (turned their life over to Christ), were Baptized, received the Holy Spirit, and were added to the church (verse 41).  There was no other requirement but what was required to become a Christian - Repentance, Baptism and receiving the Holy Spirit, which was promised to all those who would be converted to Christ. 

I Corinthians 12:13 makes it even more clear:  "For by one Spirit we were all baptized into one body...".   "Body" or "Body of Christ" with Christ as the "head" is a common metaphor used in the New Testament to refer to the church.  Salvation, receiving the Holy Spirit, becoming a part of the body of Christ (the church) all happen together at conversion.  When one has faith in Christ, and that faith leads him to repent and turn his life over to Christ to make Jesus his Lord and Savior, which leads hims to confess that faith and be Baptized to demonstrate his faith in the death burial and resurrection of Jesus for our sins - that person becomes a child of God and a part of the body of Christ, the church.

The church is simply the "assembly" of those who are saved.     We do not and will not impose any man made rules on any Christian to be a member of the Lord's church.  After all, it is the church of "Christ", not our church.  We take seriously Jesus' saying "In vain do they worship me, teaching as doctrine the commandments of men"  (Matthew 15:9).