ŚVETĀŚVATARA UPANISHAD · 6.23

यस्य देवे परा भक्तिर् यथा देवे तथा गुरौ ।
तस्यैते कथिता ह्य् अर्थाः प्रकाशन्ते महात्मनः प्रकाशन्ते महात्मनः ॥

yasya deve parā bhaktir yathā deve tathā gurau ।
tasyaite kathitā hy arthāḥ prakāśante mahātmanaḥ prakāśante mahātmanaḥ ॥

If these truths have been told to a high-minded man, who feels the highest devotion for God, and for his Guru as for God, then they will shine forth,--then they will shine forth indeed.

F. Max Müller · The Upanishads, Sacred Books of the East 15 (1884)