A reader writes:
Of course, if you envision eternity only as an endless quantity of time it becomes a horror. But that is not what the Bible means. Frederick Buechner, a wise and provocative writer, paints a different picture in his book Wishful Thinking:
When you are with somebody you love, you have little if any sense of the passage of time, and you also have, in the fullest sense of the phrase, a good time. When you are with God, you have something like the same experience. The biblical term for the experience is Eternal Life. Another is Heaven.
Eternity is not endless time or the opposite of time. It is the essence of time.
My own stab at this question from The Conservative Soul:
The precious gift of religious life lies in part, in Oakeshott's words, "in the poetic quality, humble or magnificent, of the images, the rites, the observances, and the offerings (the wisp of wheat on the wayside calvary) in which it recalls to us that 'eternity is in love with the productions of time' and invites us to live 'so far as is possible' as an immortal."
I'm reminded again of T.S. Eliot's assertion that
The point of intersection of the timeless
With time, is an occupation for the saint."
These moments may come upon us when we least expect them. We may see flashes of eternity in the simple grin of a child in a game of hide and seek, in the approach of the tide on an autumn afternoon, in the eyes of a lover in sex, or in a grandmother's ritual - but we know them when we see them. The key is to be open to them, because they happen all the time, all around us. But we are too "busy" to notice.