So, guru, there are many description. Subject matter is the same, but different way, guru has been described by different ācāryas. Their aim is the same, but language or presentation may be little different. So generally guru means:
- ajñāna-timirāndhasya
- jñānāñjana-śalākaya
- cakṣur unmīlitaṁ yena
- tasmai śrī-gurave namaḥ
- (Gautamīya-tantra)
Just like in darkness, ajñāna-timirāndhasya. Ajñāna means ignorance, "without knowledge." That is called ajñāna. So ajñāna is compared . . . ignorance, stupidity, is compared with darkness. Just like if you are . . . if this room, immediately all lights are off, then it becomes dark. We cannot see where I am sitting, where others sitting. It becomes a confusion. Similarly, in this material world we are all in the darkness. This material world is called darkness. It is called tamaḥ. Tamaḥ means darkness. Or timir. Timir means darkness. And actually, it is darkness. Because, because this material world is dark, there is need of sunlight, there is need of moonlight, there is need of electricity.
(aside) This child disturbing.
But there is another world. We get description from the Vedic literature, na yatra bhāsayate sūryo na śaśaṅko na pāvakaḥ (BG 15.6). There is another world, spiritual world, where there is no darkness, and therefore there is no need of sunlight, there is no need of moonlight, there is no need of electricity.
So guru's business is to bring out the disciples from darkness to light. That is guru's business. That is guru. First business is that because he is suf . . . everyone is suffering on account of ignorance. Just like you contaminate some disease out of ignorance. You do not know hygienic principle; you do not know that, "This thing will contaminate me. This association will contaminate me. This kind of food will contaminate me." Because we do not know, therefore we contact infection, sometimes suffer from disease. It is very simple to understand. Everyone's . . . suppose one commits something criminal due to ignorance. Due to ignorance. But in the court, when a man is criminal, in the court, if he says, the criminal, if he says that, "I did not know the law," he'll not be excused. Ignorance is no excuse. Similarly, even a child, he does not know—he catches on fire, the fire will burn. No excuse. The fire will not consider that, "Here is a child. He does not know. Excuse." No. No excuse.