MM mantra 21
Remembrance of the Supreme Personality of Godhead is the goal of all spiritual practices. One moment's remembrance of Lord Kṛṣṇa is the greatest fortune, and a moment's forgetfulness of Him is the greatest loss. Therefore even the important religious duties mentioned in this verse become null and void if they do not lead to remembrance of Kṛṣṇa. Studying the scriptures, visiting temples, observing vows—none of these is unimportant or dispensable for devotees. King Kulaśekhara, therefore, condemns them only when they are improperly performed in the name of religion. For example, the studies and meditations of the impersonalists, who deride the personal, spiritual form of the Absolute Truth, are useless. Other useless acts would include austerities performed for political ends or demigod worship aimed at winning material boons. The renunciant may become very skinny, but he will not please the Lord, and therefore he himself will not be pleased at heart. So what is the use of his austerities? As stated in the
ārādhito yadi haris tapasā tataḥ kim
nārādhito yadi haris tapasā tataḥ kim
nāntar bahir yadi haris tapasā tataḥ kim
"If one is worshiping Lord Hari, what is the use of severe penances? And if one is not worshiping Lord Hari, what is the use of severe penances? If one can understand that Lord Hari is all-pervading, what is the use of severe penances? And if one cannot understand that Lord Hari is all-pervading, what is the use of severe penances?"
The successful devotee has learned to think of the Lord in every conceivable circumstance. Thinking of Kṛṣṇa is not something to be practiced only when we are removed from our daily occupation, as in solitary meditation. Rather, Lord Kṛṣṇa instructed Arjuna to "remember Me and fight." In other words, we are meant to carry out our daily duties and at the same time think of Kṛṣṇa. Lord Caitanya's injunction to always chant the names of Kṛṣṇa is the same instruction, given in such a way that we can happily and easily follow it. In the advanced stage, a devotee effortlessly remembers Kṛṣṇa out of spontaneous love. In the beginning and intermediate stages, one can also think of Kṛṣṇa day and night, by chanting the holy name and molding one's activities in His service, under the direction of a pure devotee of the Lord.