Vaishnava Samhita. Shri Govindadasa Charitam. Vol III Book VII Chp 9 Shlokas 38 - 42

एकदा श्यामकुण्डस्य समीपे हरिमाह्वयन् |

सञ्जगौ भैरवीरागं कारुण्यरसवर्धनम् ||

तदा तत्रागतश्छन्नो वृक्षमूले क्वचिन्नृपः |

अगम्बरस्तानसेनेन श्रुत्वा शोकमवाप ह ||

आकर्ण्य भैरवीरागं सहसा करुणाकुलम् |

म्लेच्छधिपस्य हृदयं भक्तश्रेष्ठो विवेद सः ||

इतः परमिमं रागं न गास्यामि कदापि च |

इति प्रतिज्ञां विदधे भक्तश्रेष्ठो हरिप्रियः ||

अपराद्धं मया किं ते स्वामिन्निति स भूपतिः |

पप्रच्छ गोविन्ददासं विनीतो विहिताञ्जलिः ||

Once Govindadasa was singing the raga Bhairavi very melodiously and calling out for Lord Shyamasundara, sitting near the pond Govindakunda. Emperor Akbar came there at that time, accompanied by Tansen. Hiding behind a tree, he listened to the music and was greatly moved. Govindadasa, the bhakta could realise that Akbar was touched by his song in the raga Bhairavi. Immediately, he took a vow that he would never sing in future the raga Bhairavi. Seeing this, Akbar asked him very humbly what his fault was and why Govindadasa did so.