If a man (a teacher) were to receive as his fee these three worlds full of all things, he would obtain that first foot of the Gayatri. And if a man were to receive as his fee everything as far as this threefold knowledge extends, he would obtain that second foot of the Gayatri. And if a man were to receive as his fee everything whatsoever breathes, he would obtain that third foot of the Gayatri. But `that fourth bright foot, shining high above the skies', cannot be obtained by anybody whence then could one receive such a fee?