No One Comes to Christ...Unless

Jesus uttered some very solemn words: “No one can come to Me unless the Father who sent Me draws him,” emphasizing man's helplessness and utter inability to respond to Him apart from God's sovereign call. Unbelievers are unable to come to Jesus on their own initiative. If God did not irresistibly draw sinners to Christ, no one would ever come to Him.

To explain how lost sinners supposedly have the power to accept or reject the gospel of their own free will, some theologians introduce the concept of prevenient grace. Millard J. Erickson explains,

As generally understood, prevenient grace is grace that is given by God to all men indiscriminately. It is seen in God's sending the sunshine and the rain upon all. It is also the basis of all the goodness found in men everywhere. Beyond that, it is universally given to counteract the effect of sin.… Since God has given this grace to all, everyone is capable of accepting the offer of salvation; consequently, there is no need for any special application of God's grace to particular individuals. (Christian Theology, 3:920)...

http://www.macarthurcommentaries.com