SB 6.13.4
	sri-suka uvaca
	vrtra-vikrama-samvignah
	 sarve devah saharsibhih
	tad-vadhayarthayann indram
	 naicchad bhito brhad-vadhat
	Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
	Sri Sukadeva Gosvami answered: When all the great sages and demigods were disturbed by the extraordinary power of Vrtrasura, they had assembled to ask Indra to kill him. Indra, however, being afraid of killing a brahmana, declined their request.