According to Hinduism , Āratī is meant to be performed at sunrise and sunset. At sunrise the Raja-Tama predominant atmosphere present throughout the night is destroyed and the Absolute fire element frequencies of Deities arrive in the Universe. Hence, Arati is to be offered at sunrise to welcome them. The 'tārak Chaitanya' (saviour form of Chaitanya) transmitted during the arrival of the frequencies of Deities at sunrise is to be welcomed by the worshipper through the medium of the Arati (Harathi or Aarathi), whereas at sunset, the Arati is performed to destroy the Raja-Tama frequencies and to invoke the 'mārak Chaitanya' (destroyer form of Chaitanya) of the Deities. That is why Arati should be performed twice, at sunrise and sunset.
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