आब्रह्मभुवनाल्लोकाः पुनरावर्तिनोऽर्जुन।मामुपेत्य तु कौन्तेय पुनर्जन्म न विद्यते॥
ā-brahma-bhuvanāl lokāḥ punar āvartino ’rjunamām upetya tu kaunteya punar janma na vidyate
Word by word
The verse says
All the worlds, right up to the world of Brahmā, come round again, Arjuna. But having reached me, there is no being born again.
In plain words
Even heaven runs out.
That is the claim, and it is aimed at people who had organised their whole religious lives around getting there.
A very long good thing is still a thing that ends.
Where you've felt this · with money
You save for two years for a fortnight by the sea. It is everything you wanted — the room, the food, the mornings. On the twelfth day you notice you have started thinking about the journey home, and the last two days are spent somewhere between the sea and your desk.
Going deeper
Relegating heaven to the list of temporary things is one of the boldest moves in the book, and it was aimed at a live target.
The ritual system of the time worked on a clear promise: perform correctly and you earn a place in a better world. The Gita does not call that false. It calls it finite. You go, the merit is spent, you come back — an excellent holiday with a return ticket nobody mentioned.
What is offered instead is not a better destination but a different kind of thing altogether, one that is not earned and not used up.
The practical bite is closer to home than it looks. Most of us are running some version of the merit system, working toward a state we imagine will be final. The verse is not telling you to stop working. It is pointing out that no arrangement made of time has ever yet stayed arranged.