The nineteenth guru was a little child Dattatreya saw playing relaxed and untouched by the past. A child lives from moment to moment. He does not remember the past, nor does he dream of the future. All of him is present at every moment. There is no tension in play, no competition, just sheer joy and fun and celebration, like the flowering of the trees. The spiritual path too can be light and full of celebration. The sadhak should be alert against the dangers of succumbing to the heaviness of the ego. It is for this reason that santhosh, contentment, is one of the qualities of a disciple.
My nineteenth guru is the baby that cries when it is hungry and stops when it suckles at its mother's breast. When the baby is full, it stops feeding and nothing its mother does can induce it to take more milk. I learned from this baby to demand only when I really need. When it's provided, I must take only what I require and then turn my face away.