It would seem that Jesus led the twelve through distinct growth stages. If our desire is maturity, then we also need to nurture people through various stages from unbelief through to maturity.
Measuring Spiritual Maturity
Measuring people’s spiritual maturity may be something that is resisted as being impertinent. On the other hand, should we? Does good disciple-making require that we have a reasonable understanding of people’s maturity?
Measuring Maturity – Peter Cheyne – a discussion of some of the issues.