Frogs during rainy season
CC Adi 8.6, Purport: The croaking of the frogs in the rainy season resounds very loudly in the forest, with the result that snakes, hearing the croaking in the darkness, approach the frogs and swallow them. Similarly, the so-called educational vibrations of the tongues of university professors who do not have spiritual knowledge is like the croaking of frogs.
Other Books by Srila Prabhupada
Light of the Bhagavata
Light of the Bhagavata 6: On hearing the sound of the torrential rains, the frogs come out of the mountain caves and begin to chant, like brahmacārīs who chant the Vedic hymns by the order of the spiritual master
Bhagavad-gita As It Is Lectures
Lecture on BG 5.17-25 -- Los Angeles, February 8, 1969: Have you heard any sound of the frog? "Ka-ka-ka, ka-ka-ka." You have heard? (laughter) Have you heard? Yes? So what is the result of that sound? In rainy season the frogs they sing very nicely. So they like rainy season. "Ka-ka-ka, ka-ka-ka, ka-ka-ka," like that. The result is the snake can understand, "Here is a frog." He stealthily comes and immediately finishes "ka-ka-ka."
Lecture on SB 2.3.20 -- Los Angeles, June 16, 1972: Similarly, when these earholes are not receptive of the message of Kṛṣṇa, it like that, it is not being utilized properly. Similarly, you have got tongue, but you cannot chant Hare Kṛṣṇa. Jihvāsatī dārdurikeva. It is just like the tongue of the frogs. The frogs ... You have got experience during rainy season. They use their tongue very nicely. They sing ka-ka-kan, ka-ka-kan, ka-ka-kan.. (laughter) Yes. But what is the result of singing? The result of singing: in the darkness, the snakes, they can understand, "Here is a frog," and it comes and takes, immediately eats.
Initiations and Lecture Sannyasa Initiation of Sudama dasa -- Tokyo, April 30, 1972: Vacāṁsi, our talks should be always engaged in describing the glories of the Lord. That is the proper use of our talking. Otherwise, there are frogs also, they are vibrating, "kakaka, kakaka, kakaka, kakaka." That kind of vibration is simply inviting death. You know in every country there are frogs, especially in rainy season they enjoy. They think, "We are now enjoying life," by "kakaka kakaka." So the result is that the snake, in the darkness they cannot see where is the frog, but by the sound he can understand, "Here is a frog," and he comes and swallows it. So our, this talking, nonsense talking whole day and night—in the assembly, in the conference, in the business, in so many ways we are talking, "kakaka, kakaka"—the result is that we are inviting death very soon.
Letter to Tamala Krsna -- New Vrindaban 7 September, 1972: The whole world is full of darkness. The so-called yogis, swamis, mayavadis, scientists, philosophers, political leaders, all are different types of glowworms, so in the darkness of cloudy night during the rainy season, the croaking of the frogs and glitterings of the glowworms are supposed to be very prominent. But as soon as there is clear sunlight or moonlight, all these insignificant glowing and croaking disappear. So our movement is Krishna.