If you want to make progress in spiritual life, then you must make every possible effort to curb pride. Do not wait for it to go away by itself. If you do not make the effort, it will never go away.
Collected Letters to Friends and disciples Vol 4, Pg 20
Regarding your first point about preaching to the students, it is always very nice to reach out to students with Krishna consciousness. Srila Prabhupada emphasized this preaching as a great investment for the future of our movement.
Collected Letters to Friends and disciples Vol 4, Pg 14
Now apply what you've learned as a brahmacari, especially about the importance of sadhana, and mold your household life in such a way that your sadhana does not suffer. Every day there must be some chanting and hearing. This is most important for householders.
Collected Letters to Friends and disciples Vol 4, Pg 8
The strength of the great Vaisnava acaryas is their realization of the conclusive Vedic truths and because of their faith in and adherence to the previous acaryas, they are able to speak boldly without compromise.
(Lecture- SB 4.1.2, Moscow, Sept 1996)
One who has actually realized the conclusive truths of the Vedas makes his decisions in accordance with the desires of the previous acaryas.
(Lecture- SB 4.1.2, Moscow, Sept 1996)
If we want to practice bhakti, we actually have to become free from the sinful desires in the heart by the power of the Lord’s holy name.
(Lecture- Srila Prabhupada's Vyasa Puja, Alma-ata 1995)
Bhakti is the only process that can uproot the desires for sinful activity from the heart. Bhakti is so powerful because it is the most superior activity. No other process is complete until we take shelter at Krishna’s lotus feet.
(Lecture- Srila Prabhupada's Vyasa Puja, Alma-ata 1995)
The fact that Srila Prabhupada was able to make the subject matter of bhakti so easily accessible to almost anyone is proof that he was invested with Krishna-shakti. Krishna-shakti vina nahe tare pravartana: Unless one is invested with Krishna-shakti, he cannot deliver the Lord’s name to others and convince them to dedicate their lives to the chanting.
(Lecture- Srila Prabhupada's Vyasa Puja, Alma-ata 1995)
If we strictly follow our spiritual master's order, we can overcome all the imperfections that come with having accepted a material body.
(Lecture- Srila Prabhupada's Vyasa Puja, Alma-ata 1995)
If we are conscious of the order, we will be protected from the materialistic way of life. However, as soon as we forget, we have to live in this hallucination.
Caitanya Caritamrita Lectures Book, Madhya Lila, Pg 309