People betray others after gaining trust by acting disloyally for personal gain, such as by being dishonest, manipulating others, or exploiting them, which can stem from greed, insecurity, or a desire for power. There are many people who ditch for their benefit. To highlight such people, Sanskrit have said following lines ;
कृतमपि महोपकारं पय इव पीत्वा निरातङ्कः |
प्रत्युत हन्तुं यतते काकोदरसोदरः खलो जयति||
Krutamapi mahopakaaram pay iva peetvaa niraatankah.
Pratyut hantum yatate kaakodarasodarah khalo jayati.
Krutamapi = krutam + api.
Krutam = having done.
Api = even.
Mahopakaaram = great assistence.
Paya = milk.
Iva = similarly
Peetvaa = by drinking.
Niraatankah = without any fear.
Pratyuta = on the contrary.
Hantum = killing.
Yatate = tries.
Kaakodarasodarah = Kaakodara + sodarah.
Kaakodara = a snake.
Sodarh = one's own brother.
Khalo = a wicked person.
Jayati = wins, gain upper hand.
i.e. Even if a snake is shown a great favor by feeding it milk without showing any kind of fear, the snake still tries to kill the person feeding it milk. Similarly, evil people, like the snake's natural brother, do not hesitate to attack those who help them in order to gain victory.
The kindness shown to a snake is quite risky as there are chances they bite anytime. In the above Sanskrit lines ,the snake has been related with a wicked person. Wicked persons also behave like real (brothers of ) snakes, and in order to gain an upper hand do not hesitate to attack those who help them.
@queenart