I used to believe like you as a member of both a mainline CofC and the ICC and now I believe differently. There is something about that thief on the cross that's never been fully explained, at least to me. I was never of the belief that Acts 2:38 was the only scripture that counted.
Well, if you will recall, the thief on the cross died before the church was instituted on the Day of Pentecost. He died under the old law. The mission of Christ had not yet been fulfilled when the thief on the cross died. The mission/work of Christ did not finish until 3 days after the thief died. That being when Christ was raised from the dead. You cannot compare the two. They are under different dispensations. One the law of Moses, and the other under the law of Liberty/the Law of Christ.