In plain words
But by the Śāstras this is unnatural. Only from mother, father, guru and God have we the right to receive anything. But from others we must not accept any thing whatever. God is the Creator, the Sustainer, the Protector. So we have the right to receive everything from God. From our parents we must receive only according to their means and their capacity; we must not try, by going beyond the limit, to trouble even them. From the guru we must receive only learning and grace. Ko vā guruḥ? Yogahitopadeṣṭā. Towards the guru who teaches what is good, śiṣyastu ko? Yo guruvartiyevā! Apart from the way that gives him satisfaction, you must never stretch out your hand in any other way. But in the students of today this is sorely lacking. Through this alone we become subject to births of many kinds. We are turning into debtors. There is no telling how births will come to us as the fruit of this debt. Except when it is necessary, you must not eat in other people's houses at other times. You must not settle down for ten days or fifteen days, thinking, “I am at my friend's house, after all.” Your friend himself depends on his parents. He himself has no independence. In such circumstances it is not good to go and sit in their house and eat, saying, “He is my friend, my friend.” This is not what your friend earned. It is what your friend's parents earned. Only the sons have a right to the parents' earnings; others have none. In such circumstances, without weighing what is lasting and what is passing, we go and sit in other people's houses. This is not a proper habit for students. So aparigraha is most necessary. Whether a leaf, flower, fruit or water, we must be ready to offer to others any small thing. But we must not be in the least ready to accept from others. These are the human values of yama.
Then within niyama there are five niyamas. The first is śauca. The second is tapas, the third santoṣa, the fourth svādhyāya. The fifth is Īśvara-praṇidhāna. Śauca is of two kinds: outer śauca and inner śauca. Outwardly, when we want to be clean, we are cleansed by water. This cleanliness is not merely cleanliness of the body. Every thing we use in daily life must also be clean. The clothes we wear, the beds we lie on, the books we use, the house we live in: everything must be clean. Every part of the body must be clean. That is why, every day as soon as we rise at dawn, we brush our teeth, rinse the mouth thoroughly and wash the face; we must recognise that all such acts were laid down not only for health but also for joy.