God is timeless

[Medi]

You tell me, can humans grab on to the future? Can humans change the past?

No.

Possibly. Modern physics does indicate time travel is technically possible. Heck, some astronauts are fractions of a millesecond younger than they would have otherwise been due to time dilation.

Therefore, does time restrict humans to the present moment (ie, we can't travel back or forwards)?

Yes.

In principle or in practice? Travelling forwards in time is very doable; we can even do it to a limited extent nowadays, such as the astronauts I mentioned a moment ago, and we know how to do so on a grander scale, though we lack the appropriate technology.

Do we stay still in one particular present moment in time (ie, does time 'stop'?), or does each moment lead to another moment?

The latter.

Assuming a particular view of time that is inconsistent with much of modern physics as you have, then sure. Under a static view of time, such as what I hold to, there is no temporal becoming.

Therefore,

Time is a restriction on humans, (we are always physically in the present moment, not in a past moment, or a future moment). It is a concept in physics.

"Therefore"? You didn't make an actual argument, so adding that there is nonsense.
And such as you're defining it, upon time travelling I would be in a 'present moment', even though relative to when I came from I would be in the past. You seem to be confusing the first-person property of conscious experience with time here.
Not sure what concept you're talking about, especially since modern physics does NOT hold to the absolute simultaneity of time.

'Time is a restriction of physics (for humans) where one moment leads on to another'

Was that a bare assertion?

Yep.

Look, to human perception, for practical reasons related to the point I was making, we perceive the present moment. Whether we can 'travel' through time, or not, doesn't negate the fact that within our minds, we are always in a 'present'.

Our perception limits us to 'experiencing' the present moment, in the physical sense. We don't 'experience' the past in the present, though we may remember it. That actual 'moment' is part of the past. And the 'future', is something that practically, we can't 'experience', since again, our physical 'place' limits us to the present momentary experience. Even if we were 'in' the future, we would be 'present' in those future moments.

The point that I made is that christians might say this 'restriction' wouldn't apply to God.

I understand what you're saying, but I'm trying not to conceptualize time in terms of what it is in a physics book or on paper, I'm talking from humanity's literal physical 'experience' with time, and its limitations in that context.