In plain words
Place your manas in Me alone; let your buddhi dwell in Me alone. Hereafter you shall live in Me alone—of this there is no doubt.
Word for word
In Me alone place manas, in Me settle buddhi; you will dwell in Me alone from this onward; [there is] no doubt.
मय्येव मन आधत्स्व मयि बुद्धिं निवेशयनिवसिष्यसि मय्येव अत ऊर्ध्वं न संशयः
Other commentaries
The commentators
▸Bhagavadgītābhāṣyam
यतः एवम् , तस्मात् —
मयि एव विश्वरूपे ईश्वरे मनः सङ्कल्पविकल्पात्मकं आधत्स्व स्थापय । मयि एव अध्यवसायं कुर्वतीं बुद्धिम् आधत्स्व निवेशय । ततः ते किं स्यात् इति शृणु — निवसिष्यसि निवत्स्यसि निश्चयेन मदात्मना मयि निवासं करिष्यसि एव अतः शरीरपातात् ऊर्ध्वम् । न संशयः संशयः अत्र न कर्तव्यः ॥ ८ ॥
In plain words
Because this is so, then —
Fix your mind — the part of you that wavers between deciding and doubting — on me alone, this universal-formed Lord. Settle your intellect — the part that actually judges and decides — on me alone. Then what happens to you? Listen: you will dwell, you will make your home, with total certainty, your very Self grounded in mine, living in me, after this body falls away. There is no doubt about this. None. Do not let any doubt about it take root in you.
Close to the Sanskrit
Since it is thus, therefore —
On me alone, the universal-formed Lord, place, fix, the mind, which has the nature of resolve and doubt. On me alone place, settle, the intellect, which performs ascertainment. Then, what would happen to you? Listen — you shall dwell, you shall abide, with certainty, having me as [your] Self, you shall indeed make [your] dwelling in me, hence, from the falling of the body, afterward. There is no doubt; doubt should not be entertained here.