Here's my test code, I added some worksheet objects to make it a read a little easier. You have to qualify the Range
too if working from a worksheet module, if you're in a plain module you can leave it out.
sub test()
dim t as worksheet
dim one as worksheet
set t = ThisWorkbook.Sheets("t")
set one = ThisWorkbook.Sheets("1")
t.Range(t.Cells(1, 1), t.Cells(2, 2)).Value = one.Range(one.Cells(1, 1), one.Cells(2, 2)).Value
'Alternatively, what Jeeped is referencing in his comment:
with ThisWorkbook.Sheets("t")
.range(.cells(1, 1), .cells(2, 2).value = one.Range(one.cells(1, 1), one .Cells(2,2)).value
end with
end sub