According to Bible expositor Dr. John MacArthur, although Christians are supposed to be growing in Christlikeness, many are not. So Dr. MacArthur lays out the ways in which the believer can eat right and grow spiritually. He writes:
Most of us have known people whose bodies have not grown or matured properly. It’s sad to encounter people with cognitive handicaps, brain damage, or other developmental obstacles that have hindered their growth. Many of them remain locked in a child-like state—others tragically don’t progress even that far.
In a similar way, some Christians remain locked in a perpetual state of spiritual infancy. However, unlike those suffering with mental handicaps, Christians struggling with arrested spiritual development have no one to blame but themselves.