Nibbana is not an uninterrupted experience in this life, and the Buddha himself experienced serious illness. In this sense the Buddhist experience of Salvation is not unlike that of other faiths, and in particular the Arahat who has travelled the Fourth Path is like the jivan-mukti of the Hindus. But in all cases the Delivered does not cease to exist, but on the contrary rests in the confidence that what he once experienced, and could experience again, and perhaps does experience at will, is authentic and that he is set free even if the empirical consciousness remains active. Such a one moves to and fro between Byss and Abyss.
Nibbana (in early Buddhism) or Nirvana (in the Mahayana) can be summarized by the words of Jacob Boehme:
“Lastly, whereas I also said, Whosoever finds It, finds Nothing and All Things; that is also certain and true. But how finds he Nothing? Why, I will tell thee how. He that findeth it, findeth a Supernatural Supersensual Abyss, which hath no Ground or Byss to stand on, and where there is no Place to dwell in; and he findeth also Nothing is like unto It, and therefore It may fitly be compared to Nothing; for It is deeper than any Thing, and is as NoThing with respect to All Things, forasmuch as It is not comprehensible by any of them. And because It is NoThing respectively, It is therefore free from All Things; and is that only Good, which a Man cannot express or utter what It is; there being Nothing to which It may be compared, to express It by.
“But in that I lastly said, Whosoever finds It, finds All Things; there is nothing can be more true than this Assertion. It hath been the BEGINNING of All Things; and It ruleth All Things. It is also the END of All Things; and will thence comprehend All Things within Its Circle. All Things are from It, and in It, and by It. If thou findest It, thou comest into that Ground from whence All Things are proceeded, and wherein they subsist; and thou art in It a KING over all the Works of God.”
 Boehme, The Supersensual Life, “First Dialogue”.