mam kesavo gadaya pratar avyad
govinda asangavam atta-venuh
narayanah prahna udatta-saktir
madhyan-dine visnur arindra-panih
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
May Lord Kesava protect me with His club in the first portion of the day, and may Govinda, who is always engaged in playing His flute, protect me in the second portion of the day. May Lord Narayana, who is equipped with all potencies, protect me in the third part of the day, and may Lord Visnu, who carries a disc to kill His enemies, protect me in the fourth part of the day.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
According to Vedic astronomical calculations, day and night are each divided into thirty ghatikas (twenty-four minutes), instead of twelve hours. Generally, each day and each night is divided into six parts consisting of five ghatikas. In each of these six portions of the day and night, the Lord may be addressed for protection according to different names. Lord Kesava, the proprietor of the holy place of Mathura, is the Lord of the first portion of the day, and Govinda, the Lord of Vrndavana, is the master of the second portion.