The five gahs divide the day: Havan from dawn to noon, Rapithwin at midday, Uzirin in the afternoon, Aiwisruthrem from sunset to midnight, and Ushahin from midnight to dawn. The obligation at each is padyab-kusti — wash the exposed skin, untie the kusti, and recite while holding it, then retie it. The core prayers are the Ashem Vohu, the Yatha Ahu Vairyo and the Kem Na Mazda, together with the Jasa Me Avanghe Mazda, in which the worshipper declares themselves a Mazda-worshipper and a follower of Zarathustra and renounces the daevas. The whole sequence takes a few minutes. What is notable structurally is that it requires no building, no priest and no other person: the fire temple is where communal and priestly ritual happens, but the daily obligation of an ordinary Zoroastrian is portable and solitary. The prayers are in Avestan, extinct as a spoken language for over two thousand years, and the overwhelming majority of Zoroastrians learn them phonetically.