Sri Ramakrishna used to emphasize that more you dive deep you are likely to discover more and more precious gems in the realm of spiritual world. To illustrate this idea he used to narrate a beautiful story.
Once a woodcutter was chopping wood in a forest. A holy man happened to pass by who said to him, “O Man, go forward”. The words of the holy man were constantly ringing in the ears of the woodcutter. One day, going deep into the forest he discovered numerous sandal trees. He cut them and returned home with cartloads of sandal wood. He sold them and became very rich. He had not forgotten the words of the holy man. After some days, he went deeper into the forest and discovered a silver mine. This was beyond his dreams. He dug out silver from the mine and sold it for a colossal amount. After some days, he thought that the holy man had asked him to go forward, but not to stop at any point. So he went further deep into the forest and found a gold mine. He became very wealthy. But, the holy man’s advice was still fresh in his mind. After a few days, he went still deeper into the forest and found heaps of diamond and other precious stones. He collected as much of these precious items as possible and returned home. He sold them in the market and became fabulously rich.
Similarly, in spiritual life you will experience greater and greater joy and inner peace only if you go deeper and deeper into the inner recess of your heart. One should not stop even if one feels a little joy or satisfaction after doing some Sadhana. There is no end to spiritual pursuit.