Dhyana is one of the eight limbs of classical yoga. It is the penultimate limb, which leads to self-absorption (Samadhi). In some scriptures, it is considered synonymous with self-absorption. The Yoga sutras declare that meditation is helpful in steadying the mind, which is fickle by nature and which is responsible for most of our afflictions and disturbances. The object of contemplation can be anything, external or internal, the largest of the large or the smallest of small. Meditation upon the Self or God is however considered the best meditation and recommended in many traditions.
In the second section of the Yoga sutras, Patanjali further declares that the states of mind (vrittis) produced by afflictions (klesas) can be eliminated with the help of meditation. The afflictions listed in the scripture are ignorance (avidya), egoism (asmita), attachment (raga), aversion (dvesha) and longing for life (abhinivesa). Actions performed under the influence of these afflictions or the states of mind they produce lead to karma and fructify as birth (jati), span of life (ayuh) and enjoyment (bhoga) of worldly things. Hence, dhyana is also very helpful in resolving the problem of karma and ending the chain of transmigration.
Dhyana is defined in the Yoga sutras as one pointedness of the mind (eka-tanata), achieved by fixing it upon one object or image. Concentration (dharana), meditation (dhyana) and self-absorption (Samadhi) are considered the internal limbs (antaranga) of yoga practice. Their combined practice is known as samyama or an integrated practice of concentrated meditation, which leads to a heightened state of self-absorption and cessation of all mental modifications. Antarangam also means the mind or consciousness. Dhyana is very helpful in reining the mind, knowing the mind and transcending it through self-absorption.
The term 'dhyana' is used in Jainism, Dhyana in Buddhism and Hinduism, with somewhat different meanings.
Dhyāna in Buddhism: Dhyāna (Sanskrit) or Jhāna (Pali) means meditation in Hinduism, Buddhism and Jainism. In Buddhism, it is a series of cultivated states of mind, which lead to "state of perfect equanimity and awareness (upekkhii-sati-piirisuddhl)."
Dhyana may have been the core practice of pre-sectarian Buddhism, but became appended with other forms of meditation throughout its development.
Dhyana in Hinduism: Dhyāna (Sanskrit; Devanagari: ध्यान) or Jhāna (झान) (Pāli) in Hinduism, Buddhism, Jainism means meditation which is "a deeper awareness of oneness which is inclusive of perception of body, mind, senses and surroundings, yet remaining unidentified with it". Dhyana is taken up after preceding exercises, and leads to Samadhi and self-knowledge, separating māyā from reality to help attain the ultimate goal of mokṣa.
Dhyana in Jainism: Jain meditation has been the central practice of spirituality in Jainism along with the Three Jewels. Meditation in Jainism aims at realizing the self, attain salvation, and take the soul to complete freedom. It aims to reach and to remain in the pure state of soul which is believed to be pure conscious, beyond any attachment or aversion. The practitioner strives to be just a knower-seer (Gyata-Drashta). Jain meditation can be broadly categorized to the auspicious Dharmya Dhyana and Shukla Dhyana and inauspicious Artta and Raudra Dhyana.
Jain meditation is also referred as Samayika. The word Samayika means being in the moment of continuous real-time. This act of being conscious of the continual renewal of the universe in general and one's own renewal of the individual living being (Jiva) in particular is the critical first step in the journey towards identification with one's true nature, called the Atman. It is also a method by which one can develop an attitude of harmony and respect towards other humans and Nature. By being fully aware, alert and conscious of the constantly moving present, one will experience their true nature, Atman.
The 24 Jain Tirthankaras are always seen in meditative posture and have practiced it deeply and attained enlightenment.