Line 30 exclaims that the speaker should build the mansions amid the swiftly changing seasons, or because time rolls along rapidly. In line 31, the speaker tells himself to leave the "low-vaulted," or low-ceilinged, "past," and in the next line he wishes that "each new temple," a new and important metaphor suggesting the religious holiness of the chamber or house, be "nobler than the last."
The Chambered Nautilus