CS Lewis said time would probably continue in Heaven...But how?

There are at least two solid Biblical scriptures which prove that time continues in heaven. First in Revelation 19 Jesus returns in the second coming riding a white horse, we know that at that time the saved are taken to heaven for it is written

"For the Lord Himself will descend from heaven with a shout, with the voice of an archangel, and with the trumpet of God. And the dead in Christ will rise first. Then we who are alive and remain shall be caught up together with them in the clouds to meet the Lord in the air. And thus we shall always be with the Lord. " (1 Thessalonians 4:16-17)

The very next verse after Jesus return in Revelation 19, Revelation 20:1-2 says

Then I saw an angel coming down from heaven, having the key to the bottomless pit and a great chain in his hand. He laid hold of the dragon, that serpent of old, who is the Devil and Satan, and bound him for a thousand years;

Here we see a time element, a thousand years.

Also there is another verse that tells us that the seven day week will continue even in heaven for it is written

For as the new heavens and the new earth Which I will make shall remain before Me,” says the Lord, “So shall your descendants and your name remain. And it shall come to pass That from one New Moon to another, And from one Sabbath to another, All flesh shall come to worship before Me,” says the Lord. (Isaiah 66:22-23)

Herein is evidence that the seventh-day Sabbath will still be kept even in heaven. A comprehensive Christian site about this can be found here - http://www.sabbathtruth.com/

Hope that helps!

As I understand it, he is saying that our future perception may be "expanded", while still being qualitatively the same - in particular, not approaching the very different perception of time that God has. (We experience time as a succession of cause and effect; we can remember the past but can only conjecture about the future. On the other hand, God sees all times at once.)

In the letter, he talks about the thicker line as a suggestion that we could experience a "wider" present than we currently do, by being able to see and understand more things at once. However, we are still on the line, and so we have the same inability to see the future as we do now. This matches the standard account of angelic knowledge: angels' intellect is like our own, but better, so that they can make more accurate deductions about the future, but still have to deduce rather than perceiving it directly. In the same way, angels are better than us at noticing things and in the general acuity of their senses, but they still fall short of God's ability to see things as they truly are, as opposed to their being mediated by the senses.

Part of Lewis's thought in the letter is that the future "resurrection of the body" implies that we will have bodies (and senses, and minds) that are still basically the same as now. They are perfected, but are still not divine. Scholastic philosophers argued that our perception of time in heaven might be different for several reasons -

1. We couldn't measure the progression of time from our physiological processes (getting hungry or tired).
2. With no celestial bodies to look at, we can't use them to measure hours, days, seasons, or years.
3. The same goes for measuring time by the decay of objects (eg, watching an apple go rotten). That doesn't happen any more.
4. The "speed of thought" may be different, and in any case is incommensurable with what's going on in the minds of others. You can spend an amount of time thinking about something, but did it "really" take ten minutes or ten years?

This seems to match the Lewis conception of the thicker line. There is still a succession of moments, but we may perceive things differently during those moments.