Our Scripture reading today is Isaiah 45:15, "Verily thou art a God that hidest thyself, O God of Israel, the Saviour."
 
There is no doubt in Isaiah's mind of Who the one true God is.  At this point, I believe Isaiah is referring to God hiding Himself from Israel during the time of the Gentiles. (Isaiah 18:4, 40:27, 49:14; Hosea 3:3-5)  God does not hide Himself from a seeking sinner.  Even in the last days, Israel will once again seek after the one true God and they will find Him.
 
We have One Saviour to declare to this lost world, the LORD Jesus Christ.  He will always be the only way to have a relationship with God.  His death, burial, and resurrection made it possible for a sinner like me to become a saint.  Jesus Christ wants us to go and tell other sinners of the provision He made for them.