“You shall make on its (mantle) hem pomegranates of turquoise, purple, and scarlet wool, on its hem all around, and gold bells between them, all around.” (Shemot. 28:33)
The Me'il (mantle) worn by the Kohen Gadol had attached to its bottom hem 72 ornaments in the shape of pomegranates alternating with 72 golden bells. These bells tinkled to announce the Kohen Gadol's arrival in the Mishkan and his departure from it.
We learn from the fact that the Kohen Gadol's entry was announced by bells that a person should not enter even his own home unexpectedly. This shows us the importance of being sensitive and respectful to other people.
The Mishnah in Pirke Abot (4:3) states "Do not be scornful of any person." One must not insult people, verbally or otherwise. Even the most inferior person must be treated respectfully, regardless of whether you understand their issues or not.
The key to interpersonal relationships is to try and place yourself in your friends' shoes and see things from his perspective. For example, when it's hot outside and your roommate insists on the window being closed at night, try to understand his concerns - catching a cold and waking up sick the next morning. When your manager screams at you for not meeting the deadline, before you get insulted and begin to resent him, realize he must be under tremendous pressure. You'll understand him for acting the way he did since you would probably act the same way if you were under that much pressure!
Being sensitive to others can sometimes raise their spirits and affect their lives in a big way. "Although it's nice to be important, it's more important to be nice!"
Rabbi Isaac Farhi