You have to grow from the inside out. None can teach you, none can Make you spiritual. There is no other teacher but your own soul.
Growth comes from within. Until an inner realisation occurs to a person, no matter how many people tell them something, they disagree to change. Swami Vivekananda was well versed with this idea and hence he said, “You have to grow from the inside out. None can teach you, none can Make you spiritual. There is no other teacher but your own soul”.
This teaching implies that it is important for one to introspect from time to time. It is when people look within do they realise a lot about themselves, their weak areas as well as their strengths. This helps people become a better version of themselves.
Even when one wishes to walk the path of spirituality, they should first look within. Once they look within, the path becomes clear. Others cannot help them become spiritual. Others can only guide them to an extent if they are spiritually inclined already.
When you adapt the habit of introspection, you soul becomes your true teacher. There is no better teacher than your own soul. It guides you through ups and downs, making you a better person along the way.
This teaching also implies the importance of self belief. The ones who believe in themselves are the ones who are successfully able to grown from the inside out, and not vice versa. The ones who listen to their soul are the ones who have unwavering belief in their own capabilities. They do not seek external affirmation as their soul guides them through everything.