शरीरं यदवाप्नोति यच्चाप्युत्क्रामतीश्वरः।गृहीत्वैतानि संयाति वायुर्गन्धानिवाशयात्॥
śarīraṃ yad avāpnoti yac cāpy utkrāmatīśvaraḥgṛhītvaitāni sanyāti vāyur gandhān ivāśayāt
Word by word
The verse says
When the lord of the body takes a body up, and when he leaves one behind, he carries these with him, as the wind carries scents from where they sit.
In plain words
The senses and the mind are not left behind.
Krishna calls the self īśvara here - the lord, the owner of the body. Not the body's guest. Its holder.
And the picture for how it travels is the gentlest one he could have chosen. Wind over a bed of flowers. The wind does not take the flowers. It takes the smell.
Where you've felt this · in growing older
Your grandmother is eighty-six and much of what she could do has gone. She cannot manage the stairs and she stopped cooking two years ago. But she still cannot bear a badly laid table, and she will still have the last word in any argument about a neighbour. The body has handed in most of its equipment. Whatever she is made of has not changed at all.
Going deeper
What travels is not a thing, and the image of wind was chosen to say so.
A scent has no edges. You cannot carry it in your hands or set it down on a shelf. It is a quality that moves. Saying the self carries the senses the way wind carries scent means that what moves on is not equipment but leaning - the particular shape your attention has already taken.
Vāsanā, the word later teachers use for this, literally means a smell that lingers. That is not a pretty coincidence. It is the same idea, named again.
The practical edge of it is uncomfortable and fair. What you do with your attention is not a list of events that finish. It is a grain being laid down in you. Chapter 8 said the same thing about the last thought of a life: it is not a lottery, it is whatever a person has been practising all along, showing up when the pressure is highest.