Bhagavad Gita 6.16–17
Yoga is not for one who overeats or who starves, nor for one who sleeps too much or never sleeps. For the one whose food, movement, work, sleep and waking are measured, yoga becomes the destroyer of sorrow.
Bhagavad Gita 5.18
The wise see the same in a learned and humble brahmana, a cow, an elephant, a dog, and one who cooks a dog.
Bhagavad Gita 2.56
The one whose mind is not overthrown in sorrow, who does not run after pleasure, who is free from grasping, fear and anger — that one is called a person of steady wisdom.