Just as an attendant on king waits behind him and recognises his sound and utterances without even seeing the king.
Just as a gemologist knows the art of evaluating the precious stones and is able to declare whether a stone is fake or genuine by a look on its form.
Just as a swan knows how to separate milk and water and is able to do in no time.
Similarly, a true Sikh of the True Guru recognises which composition is fake and which one is genuine, created by the True Guru as soon as he hears it. He discards what is not genuine in no time and keeps it in no account. (570)