O noble ones, listen attentively to the sacred instructions regarding the observance of lunar rites and festival days, as revealed in the scriptures. When considering the proper time for performing rites, one must pay heed to the movements of the sun and the moon, especially if their setting coincides with the ritual period. The moon, when visible in the sky, is called Sinīvālī, and when it is not seen, it is known as Kuhū. For twice-born men who perform śrāddha rites with fire, Sinīvālī—the visible moon—should be chosen as the auspicious time. If the new moon day, the sacred Amāvāsyā, extends over two afternoons, or if the new moon is observed after midday, special care is required. In a fortnight where the moon is extremely waning, the following day should not be selected if it comes after the afternoon. If the waning is recent, the observance should stretch into the evening. When the lunar day is greatly increased, one must avoid those days that are joined with the previous tithi; similarly, if the increase is recent, those overlapping days should be abandoned. If the new moon day extends over two middays, this too requires attention. Now, let me explain in detail the procedure for anvādhāna, especially as it pertains to festival days. On such days, the first three tithis are to be considered, each as a quarter portion, for the proper observance. There are two midday periods to be noted, as well as the new moon and full moon days. O best of Brahmins, the prescribed time for rituals is set for either the following day or immediately, depending on the expiration of the tithi. One must understand that the immediate time or the next day is determined by the conclusion of the lunar day. When the tenth tithi is combined in observance, the merit gained spans three lifetimes. If the twelfth tithi occurs on the thirteenth day, it is regarded as superior. Should the thirteenth tithi fall at the end of the night, I will now declare the proper course: householders seek accomplishment in their rites, while ascetics desire liberation. At such a time, even if the tenth tithi is mixed, fasting should be observed on the eleventh tithi. For householders, the previously mentioned rule applies, while for ascetics, the later prescription is remembered. When the day ends, only the second tithi is prescribed for all observers. Even if not mixed, the twelfth tithi is prohibited if it follows thereafter. However, the merit of the twelfth tithi is acquired by breaking the fast on the thirteenth. The twelfth tithi may or may not occur on the thirteenth, and if the later tithi is to be observed, it should be chosen only if it is not weak. If the twelfth tithi falls on the thirteenth, how should one proceed? Some, out of devotion, say that only the second tithi should be observed with fasting; others maintain that both the twelfth and thirteenth should be observed in the same manner. There are also those who advocate for the earlier day, but that opinion is not appropriate. A householder who has a son should not perform either the breaking of the fast or the fasting itself. On the eleventh day, after eating for a full day and night, one should undertake the Chandrayana vow. If one eats when it is forbidden, he becomes equal to one who drinks liquor—such is the seriousness of the transgression. At that time, expiation must be performed by those engaged in sacrifices. This is done with the Ṛc verse "Āpyāyasva" and the phrase "having drunk Soma," O twice-born ones. In the Asatyeṃnodvaya, three mantras are recited for expiation. Whoever performs vows and similar observances obtains inexhaustible reward. Therefore, those devoted to dharma attain the supreme abode of Viṣṇu, and worldly affliction never troubles such souls. Truly, one whose soul is purified by expiation obtains the fruit of all actions.