Jesus said... My sheep hear [present tense]my voice, and I know them, and they follow [present tense]me:
Are you paying attention? Jesus defines what a Sheep is! Jesus tells us what He promises the Sheep! Being a Sheep is conditional, for they is what Jesus said! No emphasis on the promises of God, or appealing to Israel will undo, modify, void, or exempt anyone from the condition that Jesus stated clearly and emphatically!
Using Israel as an example only shows that God did not forsake His Covenant with them. It does not mean that they cannot forsake their Covenant with God! "But it is not as though the word of God has failed. For they are not all Israel who are descended from Israel; nor are they all children because they are Abraham's descendants, but: "THROUGH ISAAC YOUR DESCENDANTS WILL BE NAMED." That is, it is not the children of the flesh who are children of God, but the children of the promise are regarded as descendants."
Are you paying attention?
you are suggesting God can't keep you and, you can over ride the will of God or an act of God, as though He that made you, and made the concepts and existence of anything you can think or do, isn't as powerful as your "free will" you are defending as something more powerful then God.
by your posting its apparent you don't hear His Voice, therefore you don't get to follow. in which case if you don't know then why do you pretend to know what it is to follow? but it evident your an expert at not following and are not following otherwise you would know via experience. if you hear, then you follow, because if you don't hear then you don't believe.
one should note when Jesus was raised from the dead He revealed Himself to the faithful (trusting believers) and didn't reveal Himself to the non-believer. non-believers do not hear and do not follow. if you don't believe God is who He is and capable of what He's capable of, you believe amiss.