A great guru, who lived in a temple on the bank of a broad river had many disciples. Once he summoned them all saying that he wanted to see them before his death, which was to take place soon. The most favourite disciples of the great guru, who always lived with him grew anxious and kept themselves close to him day and night. For they thought that he might at last disclose to them the secret which made him so great. Lest they should miss the great opportunity, all of them watchfully stayed near him, waiting for the moment when the secret would be revealed. Though their guru had taught them many sacred mantras they had acquired no powers and thought that the guru still kept to himself the method that made him great. Disciples from everywhere arrived every hour and waited with great expectation.
Now a humble disciple who lived far away on the opposite bank of the river also came. However, the river, which was in high flood, was too turbulent even to allow boats to pass. But the humble disciple must not wait and tarry, as in the meanwhile the guru may pass away. But what was to be done? He knew that the mantra which his guru had taught him was all-powerful and capable of doing anything. Such was his faith. So, chanting the mantra with complete devotion he walked over the river. All the other disciples who saw this were surprised at his powers. Recognizing him as the one who came long ago to their guru and stayed but one day and went away after being taught something, all the disciples thought that the guru gave away the secret to him. They sternly demanded of their guru the reason why he deceived them thus, though they served him in every humble manner for many years, and yielded the secret to a stranger who, by the way, came only for a day long ago.
The guru, with a smile, waved them to be calm, and summoning the humble disciple to his presence, ordered him to tell the disciples what he was taught long ago. The anxious group of disciples was taken aback with amazement when they heard him utter the words Kudu-Kudu with awe, veneration and devotion. Look, said the guru, in it he believed, and thought that he got the clue to all. And even so is he rewarded for his faith, concentration and devotion. But you always doubted that it was not all and that something remained unrevealed still, though I told you mantras of great powers. This distracted your concentration, and the idea of a great secret was in your mind. You were constantly thinking about the imperfection of the mantra. This unintentional and unnoticed concentration upon the imperfection made you imperfect.