In true Biblical perspective , the opposite of SACRED is not SECULAR; but sin.
I saw NO TEMPLE therein in the City of God (Rev.21:22) means there is no distinction of things into SACRED and SECULAR, for all things and persons shall be Holy unto the Lord
So then, ” ..whatsoever ye do in word or deed, do all in the name of the Lord Jesus, giving thanks to God and the Father by him.” (Col.3:17).
Therefore even your business or job is a ministry call to the culture around you.
Just a thought!