Patañjali begins vibhūti pāda by talking about dhāraṇā. Dhāraṇā means to exercise concentration, firmness and steadfastness, which is generally called concentration, which is very important in quality meditation. In the beginning stages of meditation, it is difficult to meditate without an object. Hence Patañjali advices to have an object for meditation. At this stage, quality of meditation depends upon our ability to fix attention on the object without distraction. First, the object of meditation is to be looked at without winking. After sometime, eyes can be closed softly and the object of meditation can be seen in our mind. Our sincerity and frequency are important to see the object in our mind. This object will appear in our mind only for a short time and with persistent practice, the object can be fixed in the mind and this is called contemplation. Mind by default, always wanders. If we are able to develop our concentration, we can experience quality meditation. Practice and perseverance are important.
Meditation is nothing but fixing our attention continuously on the object that is to be known. The word continuously is important here. This continuity is explained; it is like transferring oil from one vessel to another vessel. When we transfer oil from one vessel to another, the flow of oil will be continuous and without any break. Our concentration should be like this, without any break. How to ascertain whether our meditation is good or not? In quality meditation, we feel that we have meditated only for five minutes and in reality we would meditated for over an hour. In quality meditation, we forget the place where we meditate and the duration of meditation. In higher stages, we also tend to forget about our breathing and physical body (this is known as losing of our consciousness). Here, the mind forgets about the physical body (which includes sensory organs). In this stage, we may tend to hear inexplicable sounds during meditation. It is not necessary that one should hear these sounds. Some may have this sound and others may not have. Quality of meditation does not depend upon this.
Further extension of the above stage (losing of our consciousness) is known as samādhi (trance). Samādhi cannot be practiced and has to be experienced in quality meditation. The very purpose of meditation is to enter into samādhi state. In infantile meditation, there are three categories – the meditator, the act of meditating and the object of meditation. But in samādhi, all the three become one and in fact, they dissolve into nothingness (nothingness is known as Nirguṇa Brahman). Though there are different types of samādhis, only two types of samādhis are important. They are sabīja or savikalpa samādhi and nirbīja or nirvikalpa samādhi. Bīja means seed; savikalpa means possessing variety or admitting of distinctions, differentiated, admitting of an alternative or option or doubt, optional, doubtful. In sabīja or savikalpa samādhi, there are desires in the mind in the form of a seed or seeds, which may sprout to give rise to more and more desires. That is why, it is always said that if one has too many doubts (most of them are due to inadequate spiritual knowledge) in spiritual life, he or she may not be able to meditate properly and as a result, cannot enter into samādhi state. During nirbīja or nirvikalpa samādhi, there are no seeds to sprout and hence, there will be no desires. All the desires are self-centred. When we think about others and their happiness and welfare, there is no possibility of any thoughts, whatsoever. When a person is able to stay in nirvikalpa samādhi for long period, he becomes a jīvanmukta. A jīvanmukta does not appear differently from others; he lives just like others. He dresses like an ordinary person, without saffron clothing, beads around his neck nor wears any religious signs. Attaining the jīvanmukta state is the ultimate benefit of samādhi. They are liberated during this birth, waiting for their karmas to get over. They engage themselves in serving humanity, teaching spiritual path to others, showering love and compassion on animals and birds. It is not necessary for a jīvanmukta to live in an isolated place. He will lead a normal life, eat normal food sleep normally like everyone. But, he has no ego and self-centeredness.
Further reading on different types of samādhis – GURUJI SPEAKS