Yoga means union. One aspect of yoga according to sage Patanjali is called pratyahara, which means self-control or withdrawal of the senses. In Chapter Eight of the Bhagavad Gita (verses 11 to 15), Lord Krishna gives the description of the Yoga of Self-Control that can leads us to the Supreme state. This Yoga is practiced by living a life of religious studentship through meditation.
In Chapter 8 of the Bhagavad Gita, Shri Krishna addresses an important question posed by Arjuna: How are You (the indestructible) to be realized at the time of death by those of steadfast mind? (Gita 8-2.2) In response, Shri Krishna gives a reply over several paragraphs. At first, Krishna says,
He who departs from the body, thinking of Me alone even at the time of death, attains My state. There is no doubt about it (Gita 8-5).
The Bhagavad Gita is based on a dialogue between the student, Arjuna, and the teacher, Lord Krishna. The scripture unfolds in the form of questions and answers. Prince Arjuna is paralyzed by inaction while in the midst of the battlefield of action. His doubts appear as questions, and Lord Krishna responds with explanations of various aspects of yoga to help inspire Arjuna to action. In Chapter 8 of the Gita, Lord Krishna expounds on the Yoga of the Indestructible for Prince Arjuna.