Sometimes we are asked what exactly Nirvana is and whether it is the highest spiritual state or whether there is anything beyond it. The short answer is that there are spiritual realizations and experiences beyond Nirvana. The word Nirvana in Sanskrit means ‘blown out’ as in, to blow out a candle or lamp. It refers to the extinguishing of material existence but does not refer to anything beyond that. It is most often associated with the experience of merging into what is referred to as ‘the white light’ or the ocean of light known as the ‘brahmajyoti‘. This is the stage known as brahma-bhūtarealization.
The most ancient and authentic Vedic teachings speak of 3 stages of God-realization, Brahman-realization, Paramātmā-realization and Bhagavān-realization.
वदन्ति तत्तत्त्वविदस्तत्त्वं यज्ज्ञानमद्वयम् ।
ब्रह्मेति परमात्मेति भगवानिति शब्द्यते ॥११॥
Learned transcendentalists who know the Absolute Truth call this nondual substance Brahman, Paramātmā or Bhagavān. – Bhāgavat Pūraṇa 1.2.11