Bhagavad Gita 2.53
When the intellect, bewildered by the multiplicity of holy scriptures, stands unperturbed in blissful contemplation of the infinite, then you have attained spirituality.
श्रुतिविप्रतिपन्ना ते यदा स्थास्यति निश्चला।
समाधावचला बुद्धिस्तदा योगमवाप्स्यसि॥śrutivipratipannā te yadā sthāsyati niścalā|
samādhāvacalā buddhistadā yogamavāpsyasi||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).