None of us were born adults. By God’s design, we were born helpless, unable to feed ourselves, clean up after ourselves, or even to recognize messes, danger, or harm. We were all infants at the beginning. Eventually we learned to walk, to feed ourselves, to dress ourselves, and to identify messes. We learned that some behaviors cause harm and some activities are dangerous. Over time we learned to care about other people, to protect them, teach them, and serve them. There is a progression of growth between being infant and being responsible for raising children of your own. 

There are many similarities in spiritual growth. People who place their faith in Christ also do not instantly become ambassadors who faithfully represent Christ. It usually takes time, experience, education, and community to become the kind of person that represents God well, is obedient to God’s directives, and takes on responsibility for the well-being of other people.