This is Krishna's personal guarantee — and it is one of the most reassuring verses in the entire Gita. For those devotees described in 12.6 — who offer all actions, hold Me as their goal, and meditate without division — Krishna says: I Myself become their deliverer from the ocean of death and worldly existence. And I do it quickly. No delay.
Two words carry immense weight here. 'Samuddharta' — not just a helper, but a deliverer, one who lifts you out completely. And 'na chirat' — without delay, swiftly. Like a grandfather who hears his grandchild call from across the house and drops everything to go to them — Krishna does not make His devotee wait.