God is under no obligation

"God has laid himself under no obligation, by any promise to keep any natural man out of hell one moment. God certainly has made no promises either of eternal life, or of any deliverance or preservation from eternal death, but what are contained in the covenant of grace, the promises that are given in Christ, in whom all the promises are yea and amen. But surely they have no interest in the promises of the covenant of grace who are not the children of the covenant, who do not believe in any of the promises, and have no interest in the Mediator of the covenant". ~Jonathan Edwards