In the Seventh Canto of Śrīmad-Bhāgavatam, 13th Chapter, 7th verse, Nārada Muni, while discussing with Mahārāj Yudhiṣṭhira the various functions of the different orders in society, especially mentions rules for the sannyāsīs—those persons who have renounced this material world. One who has accepted the sannyāsa order of life is forbidden to accept as a disciple anyone who is not fit. A sannyāsī should first of all examine whether a prospective student is sincerely seeking Kṛṣṇa consciousness. If he is not, he should not be accepted. However, Lord Caitanya's causeless mercy is such that He advised all bona fide spiritual masters to speak about Kṛṣṇa consciousness everywhere. Therefore, in the line of Lord Caitanya, even the sannyāsīs can speak about Kṛṣṇa consciousness everywhere, and if someone is seriously inclined to become a disciple, the sannyāsī always accepts him.
The one point is that without increasing the number of disciples, there is no propagation of the cult of Kṛṣṇa consciousness. Therefore, sometimes even at a risk, a sannyāsī in the line of Caitanya Mahāprabhu may accept even a person who is not thoroughly fit to become a disciple. Later on, by the mercy of such a bona fide spiritual master, the disciple is gradually elevated. However, if one increases the number of disciples simply for some prestige or false honor, he will surely fall down in the matter of executing Kṛṣṇa consciousness.
Similarly, a bona fide spiritual master has no business to read many books simply to show his proficiency or to get popularity by lecturing in different places. One should avoid all these things. It is also stated that a sannyāsī should not be enthusiastic about constructing temples. We can see in the life of various ācāryas in the line of Śrī Caitanya Mahāprabhu that they are not very enthusiastic about constructing temples. However, if somebody comes forward to offer some service, the same reluctant ācāryas will encourage the building of costly temples by such servitors. For example, Rūpa Gosvāmī was offered a favor by Mahārāj Mansingh, the commander-in-chief of Emperor Akbar, and Rūpa Gosvāmī instructed him to construct a large temple for Govindajī, which cost vast amounts of money.
So a bona fide spiritual master should not personally take any responsibility for constructing temples, but if someone has money and wants to spend it in the service of Kṛṣṇa, an ācārya like Rūpa Gosvāmī may utilize the devotee's money to construct a nice costly temple for the service of the Lord. Unfortunately, it happens that someone who is not fit to become a spiritual master may approach wealthy persons to contribute for temple constructions. If such money is utilized by unqualified spiritual masters to live comfortably in costly temples without actually doing any preaching work, this is not acceptable. In other words, a spiritual master needn't be very enthusiastic for constructing temple buildings simply in the name of so-called spiritual advancement. Rather, his first and foremost activity should be to preach. In this connection, Śrīla Bhaktisiddhānta Sarasvatī Gosvāmī Mahārāj recommended that a spiritual master print books. If one has money, instead of constructing costly temples, one should spend his money for the publication of authorized books in different languages for propagating the Kṛṣṇa consciousness movement.