Why Replace SATURDAY With SUNDAY

IF SATURDAY = SABBATH, WHY REPLACE IT WITH SUNDAY ??

On "Pastors's Perspective," a radio call-in show, a caller recently asked,
"If Saturday is the Sabbath, why do we worship on SUNDAY instead ??"
 Pastor Bryan Brodersen didn't beat around the bush.
He said, "Christ rose from the dead on Sunday - THAT's what we celebrate !!"
Very brief, direct - powerful !!
Its very simple:
Is Christ's RESURRECTION worth tossing out the original Saturday Sabbath ??!!
The old Sabbath celebrates God creating the universe and then resting.
Whereas the Christian Sabbath celebrates the START of CREATION
 - For Sunday = the first day of Creation Week(Genesis 1.1-3).
The creating of LIGHT = the very first thing that God created ("Let there be light," verse 3).
 Today we know that the BIG BANG fulfilled verse 3. 
So the Sunday Sabbath may eventually become the celebrating of that miracle: the BIG BANG !!
(Secondary to Christ's Resurrection, of course !!)
PS: If Gen.1.2 speaks of Earth as existing,
how can the creating of Light (verse 3) = the beginning of Creation ??!!
Verse 2 does NOT actually say the Earth was in existence !!
It says, "The Earth was VOID and FORMLESS.."

Something completely "void" is ABSENT.
Ditto for "formless." It = nothingness !! So on that basis, we can assert that nothing existed at the end of verse 2.
 God tells us that before He began creating the universe, He spoke a creative command !!
"He COMMANDED and it stood fast" (Psalms 33.6,9) !!
Since God's FIRST creative command is in verse 3 ("Let there be light !!"),
this PROVES "Let there be light !!" = the beginning of the universe !!
I rest my case.
PS: God arranged for people in Moses's day to interpret Genesis 1 one way,
but for us today to interpret it ANOTHER way.
In Moses's day they didn't know about the Big Bang, but now we do.
That's the difference !!