According to Osho, dyeing the cloth is not essential—the robe or its color has no power. What matters is the inner signal of total surrender: 'From now on—whatsoever!' Outer devices are merely catalysts to dissolve ego. If the gesture expresses wholehearted discipleship, it helps; without surrender, no ritual or robe transforms you.
The color of your clothes doesn't change you; saying yes with your whole heart does.