Aging is a quality of the physical body. Aging happens regardless of the will of a person. This applies to his entire live from birth to death.
Maturity is something completely different. It is a quality of behaviour. It may or may not happen. It happens when one is free from the traumas of the past. Any unprocessed trauma is like an anchor preventing maturity and causing one to do strange things that are looking childish.
Osho – mature men gives
“Man becomes mature the moment he starts loving rather than needing. He starts overflowing, sharing; he starts giving. The emphasis is totally different. With the first, the emphasis is on how to get more. With the second, the emphasis is on how to give, how to give more, and how to give unconditionally. This is growth, maturity, coming to you.
A mature person gives. Only a mature person can give, because only a mature person has it. Then love is not dependent. Then you can be loving whether the other is or is not. Then love is not a relationship, it is a state.”