In plain words
As for the ṛṣis: with no delusion at all about their bodies, they displayed their natural awareness of the Ātma and, with a serene spirit, stood before the people as an ideal of sacrifice, good character and courtesy. That is precisely why the āśramas where they lived were called ṛṣikul. Today, with such sacred qualities nowhere to be seen in man, and with unholy qualities such as Ahaṅkāra, ostentation, immodesty and Asatya having entered him, the letter gu has gone back. When the letter ṛ dropped out of ṛṣikul, it became ṣikul. That very ṣikul turned into iskūl, school. That is, because the schools of today have joined company with unholy qualities, the letter ṛ has vanished and only ṣikul has remained. So this is your duty today: that we win back that letter ṛ in whatever way we can, regard that first letter as the very form of the Praṇava, win it back, and set about making such sacred qualities shine forth again for Bhārata. When we think of service, we look on it as belittling, as being a servant, as if we were doing lowly work, and out of pride we hold back. Ideas of this kind can have no place whatsoever in this principle of service. If we look on it as merely trivial and petty, then here in our Bhārata the principle of the Avatāra stands clear: God Himself took on a human form to serve the world and, for the establishment of Dharma in the world, bound Himself by a vow to serve society.
Kṛṣṇa's Service, an Ideal for All
Even Kṛṣṇa, the all-pervading, the all-knowing, the all-powerful, stood as driver to His friend Arjuna and served him. Not only that: in the evening after the battle He took the horses to the stream, washed well the wounds they had taken, applied the right medicines to them, and became a cleaner who set about relieving those horses' pain. At that time Vyāsa saw it and shed tears of joy: ‘Ah! A blessing that came not even to Sanaka and Sanatkumāra has come to these horses!’