Mahabharata, the longest epic in the world, has a lot to offer to the Hindus. The various characters, each wonderful, stand as an inspiration. While those who fought from the Pandavas' side were the most inspiring, there were others too, despite having fought from the side of the Kauravas, who had a place in the heart of Lord Krishna.
Hence, they are a source of inspiration too. Lord Krishna, directly or indirectly tried to influence their decision, but in vain, as they were highly trapped in materialistic attachment, which Krishna calls illusion. Hinduism says that a man under an illusion is uncontrollable. Hence, the good pieces of advice of Krishna did not appeal to them.
One of these so-called supporters of Kauravas, but a good man, was Bhishma Pitamaha. He was the uncle of the Kauravas' father, who had sworn not to get married. He had a boon called "Iccha Mrityu". It meant that nobody would kill him. He would die only when he wished to.
When arrows from Arjuna's bow attacked him in the battlefield, he lay above them but did not die because of the boon. He wanted to witness the whole war, and therefore, decided to lie there on the bed of arrows, bearing the pain, and bleeding all over the arrows.
He was one of the most intelligent men of those times. He loved the Kauravas as his own grandsons. The art of warship was his favourite subject. He had learned a lot throughout his life and before meeting God, he wanted to shower all his learnings onto his successors.
It is believed that while on the bed of arrows, he had given some secrets of life to the Pandavas and the Kauravas. He gave some points to Yudhishtir, the eldest amongst the Pandavas, following which one could easily avoid even death. Those secrets are as mentioned below.
He had loved the art of warfare and was highly educated in it. A brilliant warrior since his childhood, he had learned by the time of old age that one should avoid violence as much as possible. The one who spreads love amongst his fellow men is dear to the almighty, and the one dear to the almighty wins protection from all the problems of life.
Truth is another factor which Bhishma Pitamah said will win the favour of the lord. The truth here relates not just to the general meaning of it. Rather, it refers to the ultimate truth. The truth that there exists a god, a supreme power, who ultimately settles the karmic accounts of all. A good man again wins his favour and never falls alone when faced with problems.
Bhishma Pitamah probably learned this through the actions of the Kauravas, who left no stone unturned to defeat the Pandavas but went on losing men from their own army. He had probably foreseen the future. Advising Yudhishtir, he says a man must avoid cheating, as it displeases God, who is the ultimate giver of justice.
History offers various examples where anger has brought destruction to many demons. It is a demonic quality. Bhishma Pitamah knew that it was anger alone that brought the Kaurava and the Pandava brothers to the Mahabharata War.
Therefore, he asked them to shed it off the moment it comes to attack them. The one who has controlled his anger has already won half the battle of life. He builds up more friendships in life. These friends support him during hard times.