Chapter 12 · The Yoga of Devotion · Krishna said
Bhagavad Gita 12.5 — The harder path
क्लेशोऽधिकतरस्तेषामव्यक्तासक्तचेतसाम्। अव्यक्ता हि गतिर्दुःखं देहवद्भिरवाप्यते ॥
kleśo'dhikatarasteṣāmavyaktāsaktacetasām || avyaktā hi gatirduḥkhaṃ dehavadbhiravāpyate ||
Meaning
But the struggle is greater for those whose minds are set on the unmanifest. For embodied beings, the path to the formless is reached only with great difficulty.