In just four short lines, the poem sets two things side by side: new life and a failing heart. The phrase "new life" could point to spring, a birth, or a fresh start, but it lands "in a weak heart," so the beginning is tied to something worn out. The title, "Deferment," suggests a delay, a putting-off. Here, what's being put off seems to be death.
The speaker's tone is quiet and a little wry. The heart "would be glad to find / some time to go" is an odd, gentle way to talk about dying. It's phrased like someone looking for a free afternoon to leave, not someone fighting to stay. There is weariness in that, but also a strange politeness, as if departure were an errand to schedule. The poem never says whether the speaker is speaking of themselves or of someone else, and that ambiguity keeps it open. The mood is hushed, tired, and tender, with a trace of dark humor, and the unresolved final line leaves the wish hanging.