"Manurbhav" is a very brief but powerful hymn (sukta) from the Rig Veda. Its simple meaning is "Oh Man, Be a Man". It conveys a grand human goal. When it comes to food, sleep, fear and indulgence in sensual enjoyment for the furthering of the one's race, there is no difference between a man and the other creatures like animals, birds and sects. The only thing that separates us from all other creatures is our capacity to think and act and be sensitive to the feelings of others.
Do as you would be done by, is the essence of "manurbhav". This thinking can help us regulate our actions in daily life. For example, you are an officer who has public dealings, and on a particular day when you are very busy, you are told that an aggrieved person has come to meet you from a distance of 300 km. You have two options. First, which generally happens, you ask your P.A. to tell him that you are very busy and can see him only the next day.
Another option is that you put yourself in his shoes and give a thought to what your state of your mind would be if you get such a reply when you approach some authority. Stretch your mind further to think how the other man will have to spend money on his stay and he would be wasting a full day for a matter that would probably need five minutes from you. And it is quite possible your patient hearing may save him from passing another day in a state of distress. When you start thinking like this, you raise yourself above other creatures and qualify to be called a human being.
Nor is it necessary that only by giving some money can we share another's sorrow. Even a sympathetic look, a patient hearing, a few words of love, the holding of trembling hands which are looking for some support can work wonders. But in sharing, we become a “Man” as enshrined in Vedas.