Prabhupada: … [I]f you ignite wood for fire, if the wood is dry, the fire takes place immediately, and if it is moist, then it takes time. Only smoke will come. So smoke is not required. The blazing fire required. Then if from the wood, if simply smoke comes you cannot (chuckles) take any work out of it. There is traces of fire. As soon as there is smoke, there is fire, but it is not useful. It is useful for troubling your eyes only. What is smoke?

Smoke means also fire. But you require blazing fire, not smoke fire. So blazing fire takes place if the wood is dry, immediately takes place.

Otherwise, you go on enjoying the smoke. Be satisfied. “When there is smoke, there is fire.” But it will not be useful. (chuckling) It will be useful, gradually the wood will dry. It takes long time. Just try to understand this example. You require the flame, not the smoke. But if you are satisfied with the smoke, that is your business. If you simply be satisfied—”The smoke is also fire. Unless there is fire, why the smoke comes?”—that’s a good argument, but smoke will not help you. You require the flame. That flame cannot be produced if the wood is wet. Wet means materially contaminated.

… So pure devotional service is flame. All other things are smoke. You must get the flame. Otherwise, your business will not get done.

Room Conversation with Bhurijana Dasa and Disciples — — July 1, 1974, Melbourne