the oldest and longest of the Upanishads, the Brihadaranyaka says:
"From the unreal lead me to the real!
From darkness lead me to light!
From death lead me to immortality!"
The crux of the Upanishads is that this can be achieved by meditating with the awareness that one's soul ("atman") is one with all things, and that "one" is the Absolute ("Brahman"), which becomes the "all".
dipika duggal