Some leaders of the Church of Christ transgress the Word of God by their tradition on placing membership, they also transgress the commandment of God by accepting those who's baptism is invalid. If a man or woman comes with letters of commendation from a Baptist church or any man made church and places formal membership and they accept them by their tradition his or hers sins are still on them from the Word of God. Baptism saves us; 1 Peter 3:21 and that Baptism can not be invalid. To add or to omit anything, may EXCLUDE from life everlasting. Paul said; in Romans 6:17&18, we where saved when we obeyed from the heart that form of doctrine which was delivered you which Baptist do not believe the the apostles' doctrine,( most of them tell you to have a sincere desire to receive Jesus into your heart as your personal Lord and Savior, then talk to God from your heart AND THAT WILL SAVE YOU). Most of the other man made bodies don't even know what the APOSTLES' DOCTRINE is!
Can one's baptism be invalid? To answer this question let's turn to Acts 19:1-5. Paul found some disciples in Ephesus who had "not so much as heard whether there be any Holy Ghost." When Paul asked them unto what were they baptized they responded, "Unto John's baptism." Paul explains to them the purpose of John's baptism in verse 4. Notice the response of these disciples as recorded in verse 5: they were "baptized in the name of the Lord Jesus" upon hearing Paul's words. In these verses we see that one may be baptized, and have their baptism be invalid. These disciples saw the need to be baptized again once they had learned the truth. John's baptism ceased to be in effect once Christ died on the cross and the church was instituted. Just as these people needed baptized in the name of the Lord Jesus once they heard the truth, people today who are baptized in response to false teaching need to submit to baptism in the name of Jesus to have their sins washed away. If one hears and believes error, they will not be baptized for the right reasons. Once they hear and believe the truth, they must repent of sins, confess the name of Jesus before men, and be baptized for the remission of sins in order to enter a saved state