Guru Nanak's Tapas and Meditation

In order to realise God quickly Nanak practised rigorous meditation. He was always in a deep meditative mood. He did not care for his body. The parents thought that Nanak was ailing seriously and so they sent for a physician. Nanak said to the doctor: "You have come to diagnose my ailment and prescribe medicine. You take my hand and feel the pulse. Poor ignorant doctor, you do not know that the pain is in my mind. O doctor! Go back to your house. I am under God-intoxication. Your medicine is of no use to me. Few know my disease. The Lord, who gave me this pain, will remove it.

I feel the pain of separation from God. I feel the pain which death may inflict. O ignorant doctor! Do not give me any medicine. I feel the pain that my body will perish by disease. I forgot God and indulged in sensual pleasures. Then I had this pain. The wicked heart is punished. If a man repeats even a portion of the Name of the Lord, his body will become like gold and his soul will be rendered pure. All his pain and disease will be annihilated. Nanak will be saved by the true Name of the Lord. O physician! Go back to your house. Do not take my curse with you. Leave me alone now".

He concealed himself in the forests for days together.Nanak gave up food and drink for some days. He became wholly absorbed in divine contemplation. He observed perfect silence.