Psalms 27:5
כִּי יִצְפְּנֵנִי בְּסֻכֹּה בְּיוֹם רָעָה יַסְתִּרֵנִי בְּסֵתֶר אָהֳלוֹ בְּצוּר יְרוֹמְמֵנִי
Because He conceals me in His shelter on the day of evil, He hides me under the cover of His tent, He will raise me upon a rock.
Psalm 27 (l’David) is recited daily from Rosh Chodesh Elul through Shemini Atzeres. This verse, with its reference to a succah, is the source of our practice to recite this psalm throughout Succos. This is not the context of the verse, however. The ibn Ezra says that the shelter is Jerusalem. Rashi is even more precise: he says that the shelter is specifically the Temple.