The following episode appears in Śrīla Prabhupāda-līlāmṛta:

One time, ten hippies from the Millbrook commune came to Swamiji’s kīrtana. They all chanted—not so much in worship of Kṛṣṇa, but to see what kind of high the chanting could produce.

After the lecture, a Millbrook leader asked about drugs.

Prabhupāda replied that drugs were unnecessary for spiritual life, that they could not produce spiritual consciousness, and that all drug-induced religious visions were simply hallucinations.

“But have you ever taken LSD?” The question now became a challenge.

“No,” Prabhupāda replied. “I have never taken any of these things—not even cigarettes or tea.”

“If you haven’t taken it, then how can you say what it is?” The Millbrookers looked around, smiling. A few even laughed and snapped their fingers, thinking the Swami had been checkmated.

“I have not taken,” Prabhupāda replied regally from his dais. “But my disciples have taken all these things—marijuana, LSD—many times, and they have given them all up. You can hear from them. Hayagrīva, you can speak.”
Hayagrīva sat up and declared:

“Well, no matter how high you go on LSD, you eventually reach a peak, and then you have to come back down. It’s like traveling in a rocket. You can go very far, but eventually you must land.
But with Kṛṣṇa consciousness, you don’t come down. You stay high forever.”

High Forever???

In the early stages, Kṛṣṇa consciousness feels like a joyride. One feels one could stay high forever. But as days pass, one realizes it’s not so easy.

Technically, a devotee never comes down from the stage of bhāva, the eighth level of the nine stages of devotional service. At that stage, one can truly stay high forever.

But most practitioners are on lower stages of bhajana-kriyā and anartha-nivṛtti (third and fourth stages). Here, ups and downs are a regular feature. A devotee is accustomed to not only looking out for maya, but also seducing and embracing her at times. (Maya includes everything temporary – that which is not. We hold on to our opinions, to our ideas, our desires, our longings and so on. Sometimes, maya comes in the form of distractions, other times in the form of loosening our guard in Krishna Consciousness, yet other times by making us hopeless and many other ways.)

So how can one stay high forever?

High in Spirits:

A devotee may not always be free from māyā’s attacks, but they can remain high in spirit. Maya may be ruthless, but a devotee’s firm hope is Krishna’s causeless mercy.

The cataka bird always looks for the swati nakshatra rain. Even if she falls in the Ganges due to thunderbolt striking her, she keeps her beak above, not wanting to drink even the Ganges water. Such is her determination!

A devotee, in the same way, looks forward ONLY for Krishna’s grace in his or her life.

Mahārāja Pratāpa-rudra had a vast kingdom and all comforts of royalty. But he felt his life incomplete without the mercy of Mahāprabhu.

yadi more kṛpā nā karibe gaurahari
rājya chāḍi’ yogī ha-i’ ha-iba bhikhārī
If Gaurahari, Lord Śrī Caitanya Mahāprabhu, does not bestow His mercy upon me, I shall give up my kingdom and become a mendicant, begging from door to door.
(Cc. Madhya 13.8)

Seeing his intense eagerness, the devotees petitioned Mahāprabhu. And when the Lord saw the king personally sweeping the road in humility, He resolved to bless him.

rājāra tuccha sevā dekhi’ prabhura tuṣṭa mana
sei ta’ prasāde pāila ‘rahasya-darśana’
Śrī Caitanya Mahāprabhu was very pleased to see the king humbly engaged in menial service, and due to that humility, the king received the Lord’s mercy and could witness His confidential pastimes.
(Cc. Madhya 13.60)

Pratap Rudra was always high in his spirits of attaining Mahaprabhu’s lotus feet. And consequently, he became an object of Mahaprabhu’s affection. 

High in Sadhana

Even after receiving maya’s countless thrashings, a devotee must remain high in sadhana. In fact, deep sadhana enables a devotee to resists maya’s temptations.

Mayadevi herself couldn’t seduce Haridāsa Ṭhākura because of his determination to chant 192 rounds daily.

We may not imitate him, but can we not fix a realistic weekly sadhana quota? Whenever maya tempts us, we can procrastinate her in her attempts to distract us from our real goal of life.

High in Association

Sometimes, even with high spirits and completing our sadhana, we may not remain high. Because, maya’s determination to thwart our attempts is also high!

Sometimes, she enters our sadhana unnoticed. We may begin streaming something in the name of Kṛṣṇa-kathā and end up indulging in mayic content. What begins with an innocent quest for self enlightenment becomes a rendezvous with sense gratification.

That’s why we need high association; contacts to dial during a spiritual emergency, like dialing 100 or 101 for fire or ambulance services. Whenever consciousness catches fire or needs ICU attention, we must unhestitatingly and urgently take to the right association. 

The power of association can lift our consciousness even when it is low. Exalted devotees possess within them a great intoxicating nectar or beverage. And they infect us with that nectar.

Dhruva Mahārāja was burning with anger, but the association of his mother and Narada Muni transformed him.

Ajamila was totally contaminated by the association of prostitute, but the momentary association of Vishnudutas changed his life.

Narada Muni’s four months of association with Bhaktivedantas sustained him for the rest of his life. He took that association and kept the memories deep within.

Someone may ask, what if the same association ditches us? Or in other words, what if we receive improper treatment from devotees? Can we decide once and for all to directly surrender to Krishna without keeping the devotees in between?

Actually, surrender to Krishna is not possible without surrendering to devotees. We may avoid, or respect from distance the devotees with whom we are unable to go well; but in general, we have to bind ourselves to the principle of taking association of devotees. As Narottama dāsa Ṭhākura says, chāḍiyā vaiṣṇava-sevā nistāra pāyeche kebā.

There cannot be an highs in our devotion without association.

Thus, when we align our spirits, sadhana and association, we can stay high in spite of the ‘lows’, and ultimately, by the grace of Hari, guru and Vaishnavas, attain a stage where we can truly stay high forever!