Bhagavad-gītā As It Is · Text 12.5
Krishna describes devotional practice and progression
क्लेशोऽधिकतरस्तेषामव्यक्तासक्तचेतसाम् ।
अव्यक्ता हि गतिर्दु:खं देहवद्भिरवाप्यते ॥ ५ ॥
kleśo ’dhika-taras teṣām
avyaktāsakta-cetasām
avyaktā hi gatir duḥkhaṁ
dehavadbhir avāpyate
For those whose minds are attached to the unmanifested, impersonal feature of the Supreme, advancement is very troublesome. To make progress in that discipline is always difficult for those who are embodied.
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