What shall we say then that Abraham our father, as pertaining to the flesh, hath found? For if Abraham were justified by works, he hath whereof to glory; but not before God. For what saith the scripture? Abraham believed God, and it was counted unto him for righteousness. Now to him that worketh is the reward not reckoned of grace, but of debt. But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness.This event happened well before Abraham offered up Isaac. That's how it is. Believers are justified by faith first, after the Lord opens their heart. Then, because they have true faith, they act on it. So of course they are obedient. This is not really that hard.
(Romans 4:1-5)
Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be. So then they that are in the flesh cannot please God.OK, maybe not hard. Paul is really saying it's impossible. Which is what I suspect is behind most systems that emphasize legal performance over faith and the new birth. Campbellism is a great example. If the supernatural work of the Holy Spirit in regeneration has been written out of the script, what else is there but human performance? But why is the Holy Spirit's role in conversion eliminated in this way? I think it is because of a deep-seated fear of the inability to control Him. That's not a good feeling for most folks. As natural humans, we want some five step formula to deal with our needs. It doesn't matter if it's easy or hard, as long as we can control it.
(Romans 8:7-8)
You’re right about the false dilemma. But it’s not in what Jesus said concerning those whose hearts were far from God.
Rather, the false dilemma is between Abraham’s faith and his obedience. You see, faith is obedient.
Those God rebuked through Isaiah, and whom Jesus rebuked in the passage in the OP, claimed to have faith, honoring God with their lips. But their hearts were so far from Him that their worship was mere man-made commandments.
Abraham wasn’t like that. His heart drew nigh unto God; he obeyed God; he trusted and believed God. When God told him to leave Ur of the Chaldees, he did it. When God gave him a promise, he believed it. When God told him to sacrifice Isaac, he did it. When God commanded, he obeyed.
Some people today want to say, “I have faith, but I don’t want to obey.” Was Abraham like that? No. Jesus called such people hypocrites, merely honoring God with their lips.