Spiritual cause
Bhagavad-gita As It Is
BG Chapters 1 - 6
Some people are too materially attached and therefore do not give attention to spiritual life, some of them want to merge into the supreme spiritual cause, and some of them disbelieve in everything, being angry at all sorts of spiritual speculation out of hopelessness
BG 4.10, Purport: Furthermore there are many persons who cannot understand spiritual existence at all. Being embarrassed by so many theories and by contradictions of various types of philosophical speculation, they become disgusted or angry and foolishly conclude that there is no supreme cause and that everything is ultimately void. Such people are in a diseased condition of life. Some people are too materially attached and therefore do not give attention to spiritual life, some of them want to merge into the supreme spiritual cause, and some of them disbelieve in everything, being angry at all sorts of spiritual speculation out of hopelessness. This last class of men take to the shelter of some kind of intoxication, and their affective hallucinations are sometimes accepted as spiritual vision.
Srimad-Bhagavatam
SB Canto 3
The intelligent men, the brāhmaṇas, were engaged in advancing the spiritual cause
SB 3.21.52-54, Purport: Real advancement is advancement toward spiritual realization, and the community which acted toward this end was known as the Āryan civilization. The intelligent men, the brāhmaṇas, as exemplified by Kardama Muni, were engaged in advancing the spiritual cause, and kṣatriyas like Emperor Svāyambhuva used to rule the country and insure that all facilities for spiritual realization were nicely provided.
SB Canto 6
The theist, who accepts the Supersoul, finds the spiritual cause through mystic yoga
SB 6.4.32, Translation: There are two parties—namely, the theists and the atheists. The theist, who accepts the Supersoul, finds the spiritual cause through mystic yoga. The Sāṅkhyite, however, who merely analyzes the material elements, comes to a conclusion of impersonalism and does not accept a supreme cause—whether Bhagavān, Paramātmā or even Brahman. Instead, he is preoccupied with the superfluous, external activities of material nature. Ultimately, however, both parties demonstrate the Absolute Truth because although they offer opposing statements, their object is the same ultimate cause. They are both approaching the same Supreme Brahman, to whom I offer my respectful obeisances.
Conversations and Morning Walks
1973 Conversations and Morning Walks
There is only one cause. Only one cause. But they are manifested in two, material and spiritual
Morning Walk -- April 29, 1973, Los Angeles:
Prabhupāda: Cause of all causes.
Svarūpa Dāmodara: That, the two causes, are not very clear. The material and instrumental.
Prabhupāda: Hmmm?
Svarūpa Dāmodara: The two types of causes, the relative...
Prabhupāda: There is only one cause. Only one cause. But they are manifested in two, material and spiritual. Cause is one. But they are manifested in two; one is material, one is spiritual.
Svarūpa Dāmodara: So the instrumental is the spiritual?
Prabhupāda: Eh?
Svarūpa Dāmodara: The instrumental cause...?
Prabhupāda: Yes. Efficient cause. Maybe. Which is actually acting.
Karandhara: Just like the material cause of the ocean is the rain.
Prabhupāda: Hmmm?
Karandhara: Or the material cause of the rain is the ocean. The efficient cause, the spiritual, the original cause was Kṛṣṇa because He created the material energy.
Prabhupāda: Yes. yes.1976 Conversations and Morning Walks
Either you say material cause or spiritual cause, but you are suffering what you did not want. That is the point
Garden Conversation -- June 28, 1976, New Vrindaban:
Whatever it may be, you did not want; you have it—against your will. This is your experience. There is no difference. Either you say material cause or spiritual cause, but you are suffering what you did not want. That is the point. You are suffering. And you did not want it. Yathā duḥkham ayatnataḥ. Nobody wants distress, but it comes. How it comes? Yathā duḥkham ayatnataḥ, Prahlāda Mahārāja... Ayatnataḥ means without any endeavoring. Who is trying that "Let there be fire in my house"? But it takes. Nobody wants that "There may be fire in my house," but there is fire. Therefore you have to arrange for fire brigade. You are expecting always some danger. Therefore you make so many precautions, because you know that although you do not want mishappening, it will come. Nobody endeavors for mishappenings, but you know there is some superior force who'll enforce mishappening. And they are unable to counteract. Just like a scientist knows that he'll die, but he's so expert scientist that he cannot counteract. He knows that he'll die. He's talking all nonsense while living, but he does not make any arrangement that he'll not die. That he is unable. They are making arrangement, going to the Mars planet at the expense of taxpayer, so if we request these rascal scientists that "You discover something so that we will not die. Take any amount of money," will they able?