Asato maa Sadgamaya
Tamaso maa Jyotirgamaya
Mrityorma Amritam gamaya
Om Shantih, Shantih, Shantih
From untruth to truth
From darkness to light
From death to immortality
(From the transient world of decay lead me to the everlasting world of Bliss. Let the effulgence of Thy Grace illumine by being with Truth. Save me from this cycle of birth and death and destroy the craving of the mind, which produce the seeds of birth).
Explanation with example
When the room is dark, we stumble and fall; we are terrorized by imaginary fears; a number of insects move about freely and make us uncomfortable. When we put on the light, we are comfortable and happy, so also when our minds are dark, the pests of Moha, Lobha, Mada, Matsarya, Kama and Krodha trouble us and make our lives miserable. So we pray to God to illumine our minds.
Ignorance is like darkness. In this darkness, we fail to see that we are all related to one another and to God, by the kinship of Atma. This gives rise to greed, envy, jealousy, hatred and anger. These evil tendencies make our lives miserable. Hence we pray for the light of Jnana, which dissolves all the differences.
When the Lord is pleased with us, what boon will we ask him to grant us? To pass us in an examination? Or to give us lots of money? Then what else? The only treasure in this world that one should possess is true knowledge and the knowledge is light: That knowledge is self-realization.
Once there lived a king called Uddalaa. He was once performing a yajna. In that sacrifice, he was giving away a lot of wealth, cows, etc. His little son Nachiketa was sitting by his side and was observing all that was going on. Though young in age, he was very intelligent. He understood the vanity and deceit of his father, in giving away all the barren cows. He felt a great pain heart. In order to save his father from sins, he asked the father, "Oh! My dear father! To whom are you giving me away?" The father didn't reply for some time. When asked repeatedly, he got angry and said "My son, I am giving you away to Yamaraja". Nachiketa was very pleased. He at once went to the abode of Yamaraja. But to his great disappointment Yamaraja was not in Yamapuri. He had gone out for some urgent work.
Nachiketa had to wait for three days and three nights at the door of Yamaraja's palace. At last on the fourth day Yamaraja returned. Seeing this little boy at his gates, Yamaraja was quite amused. He offered the boy three boons, as the boy had to wait for three days. The first boon Nachiketa asked for was to forgive his father for his ignorance. The second one was to cool his father's anger. And the third one was to bestow upon him the knowledge of self-realization. Lord Yama didn't want to grant the third boon. He tempted the child with many worldly attractions and pleasures. But nothing could change the child's mind. His only prayer was Mrityorma Amritam Gamaya.
He wanted to go from mortality to immortality. At last seeing the child's perseverance, Lord Yama had to grant the boon to Naciketa.
We too mustn't ask for worldly pleasures, as they are all just temporary. But immorality is everlasting.