a true friend should be like a father.

न तन्मित्रं यस्य कोपाद्बिभेति

यद्वा मित्रं शङ्कितेनोपचर्यं।

यस्मिन्मित्रे पितरीवाश्वसीत

तद्वै मित्रं संगतानीतराणि॥३५

श्रीमहाभारते उद्योगपरवणि प्रजागरणपर्वणि विदुरनीतिवाक्ये अध्यायः ३६

na tanmitraṁ yasya kopādbibheti

yadvā mitraṁ śaṅkitenopacaryaṁ|

yasminmitre pitarīvāśvasīta

tadvai mitraṁ saṁgatānītarāṇi||35

śrīmahābhārate udyogaparavaṇi prajāgaraṇaparvaṇi viduranītivākye adhyāyaḥ 36

Yet another ever-relevant statement from Vidura in his Neetivakyam..

" If you have to be always vigilant about the anger of a person and try to adjust according to his mood changes, then that person is not a friend of yours.  He is also not a good friend if  you have to serve with circumspection, fearing the loss of friendship and the consequent personal losses.  The true friend is one to whom you can go for succour and relief, as if you are approaching your own father.  Other relations are merely time-serving and ad-hoc connections."

True, a father is the most genuine friend for anyone.  When it comes to the problems of one's own son, personal interest simply vanishes, as far as a father is concerned.  A father will be ready to stake anything in his possession including his own life for the sake of his son.  If one can get a friend of that closeness, one is really fortunate. Krishna and Arjuna were like that. 

Damon and Pythias  were  also like that. I extract the story of their friendship in brief. The story is well known but it is worth a few seconds' time to recall.

As told by Aristoxenus, and after him Cicero (De Offic. 3.45), Diodorus Siculus (10.4), and others, around the 4th century BC, Pythias and his friend Damon, both followers of the philosopher Pythagoras, travelied to Syracuse. Pythias was accused of plotting against the tyrant of Syracuse, Dionysius I. As punishment for this crime, Pythias was sentenced to death.

Accepting his sentence, Pythias asked to be allowed to return home one last time, to settle his affairs and bid his family farewell. Not wanting to be taken for a fool, Dionysius refused, believing that once released, Pythias would flee and  would never return.

Pythias called for Damon and asked him to take his spot while he went. Dionysius agreed, on the condition that, should Pythias not return when promised, Damon would be put to death in his place. Damon agreed, and Pythias was released.

Dionysius was convinced that Pythias would never return, and as the day Pythias promised to return came and went, Dionysius prepared to execute Damon. But just as the executioner was about to kill Damon, Pythias returned.

Apologizing to his friend for his delay, Pythias told of how pirates had captured his ship on the passage back to Syracuse and thrown him overboard. Dionysius listened to Pythias as he described how he swam to shore and made his way back to Syracuse as quickly as possible, arriving just in time to save his friend.

Dionysius was so pleased and astonished with their friendship that he pardoned them both.

 We find bosses and persons placed in influential positions declaring that all the people who are in their circle are their friends.  But if any person who is beholden to them acts in a way that will arouse their anger even slightly, they punish them and simply forget the much-touted  friendship. There are others who will keep people as friends so long as it is advantageous to their personal interest and if the utility of the professed  friend is not substantial any more, they discard him like torn rags.  But a true friend never forsakes his own friend at any cost. 

Vidura has taken the example of one's own father.  A father will be both affectionate and caring to the son and also will be aware of things which will add to the benefit of the son.  A mother is more emotional, and protective but she may not be able to visualize the benefits for her child in the long-term perspective like the father, because her love for the offspring often transcends reason.

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