Calvinism makes God the author of sin

  The Calvinistic interpretation of God hardening the heart of the Pharoah , so that he ends up sinning , makes God the author of sin.Similairly , by hardening the hearts of  majority of humans and allowing them to remain in the sin of unbelief , God becomes the author of sin according to Calvinism. Though they may not tell this not accept this , that's what it means.
  Bible clearly teaches that God neither tempts nor is tempted. God is very clear in that he does not endorse sin. So he does not randomly choose to harden a human being , to bring glory to himself. He hardens only those who harden themselves repeatedly and resist his work intentionally.
  It was Pharoah who hardened himself initially and repeatedly and then God hardened him as a judgement for his resistance , inspite of overwhelming evidence of the power and awesomeness of God.
  If everything is under God's sovereign will , without any choice for humans ,earth would be heaven. God's sovereign will  has given free will to man , whom he created in his own image . The fall did not destroy free will altogether, so much so that God has to choose few to be saved and send the majority to hell. God loves man so much that , if it did not require human choice , he would have chosen everybody to be saved. He would never have let Adam fall into sin. He would never even let lucifer become the devil. But that's not so . It is because , God wants man , whom he made in his image , to respond to him as he works in their life. He wants man to seek him and know him as Saviour and Lord.

    As Paul said to the Athenian crowd ,
  "26From one man he made every nation of men, that they should inhabit the whole earth; and he determined the times set for them and the exact places where they should live.27God did this so that men would seek him and perhaps reach out for him and find him, though he is not far from each one of us. 28‘For in him we live and move and have our being.’ As some of your own poets have said, ‘We are his offspring.’ "

God has set everything in place so that men would seek him and know him ,ofcourses the spirit of God working althrough in the midst of everyone. 

 If it was God's sovereign will that only a few be saved and the rest be damned , he would have told us that plainly as the calvinsts tell us today . God would clearly communicated that in his word. But it is not so. 

This verse  "we are his offsprings" ,calls unbelievers also God's offspring , only that their relationship with God their father is broken and they don't know how to find their way back to their heavenly Father. These estranged children , strangers to their own Father can be reconciled back to their Father God only through Jesus Christ. 

So God's Sovereign will for everybody is Salvation through faith in Christ according to the Gospel . He does not harden anyone to sin and then consequently send them to hell also , having already allowed them to be born with a sinful nature ,though they are image bearers of God. 

Do away with the nonsense of Calvinsim, the lie which contradicts God and the Scripture and seek the truth. God will certainly reveal that to you, if you do that with an open heart.