Throughout his life Balaram, like other Vaishnavas, was a believer in ahimsa, nonviolence. He had even thought it wrong to kill the mosquitoes that disturbed his meditation. But after associating with Sri Ramakrishna for a couple of years he realized that the most important thing in spiritual life is to keep the mind in God. Thus, killing a few mosquitoes for the sake of steady meditation should not be considered a sin. His orthodox upbringing, however, made him doubt this reasoning, and he found himself in a real dilemma, so he immediately left for Dakshineswar to lay the problem before the Master.
Arriving at Sri Ramakrishna’s room, he noticed to his great surprise that the Master was busy killing bedbugs. As Balaram approached him and bowed down, the Master said: “There are many bedbugs breeding in the pillow. They bite me day and night, create distraction of the mind, and keep me from sleeping, so I am killing them.” Thus Balaram’s question was answered by the Master. Furthermore, he understood that though he had been visiting the Master for two or three years and observing him closely day and night, the Master had never done anything that might hurt his feelings or disturb his faith. He had waited to teach Balaram this lesson until he knew that Balaram had enough faith in him to be able to accept it. (Source: They Lived with God)