My 20 year old niece who was saved and baptized in a Baptist church started dating a Mormon boy 2 months ago. Last week she announced she was becoming Mormon and was baptized Mormon. Does that mean she loses her salvation? Is that considered rejection of the Holy Spirit?
It’s impossible for a believer to lose his or her salvation, so we have to consider other possibilities. Maybe she wasn’t really saved after all. Only she and the Lord know for sure. More likely she doesn’t fully understand official Mormon doctrine, thinks it’s another Christian religion, and doesn’t see anything wrong with converting.
If she was truly saved she belongs to the Lord, and He will not let her be lost. There are several places in the Bible that promise once we belong to the Lord, nothing can take us away from Him. Ephes. 1:13-14, 2 Cor. 1:21-22, John 6:38-39, John 10:27-30, and Romans 8:38-39 are examples of this promise.