“Brethren, my heart’s desire and prayer to God for Israel is, that they might be saved. For I bear them record that they have a zeal of God, but not according to knowledge. For they being ignorant of God’s righteousness, and going about to establish their own righteousness, have not submitted themselves unto the righteousness of God. For Christ [is] the end of the law for righteousness to every one that believeth” (Romans 10:1-4).
Tolerant Calvinist: Paul, the reason I have no problem affirming that many zealous-yet-ignorant Israelites truly know the Lord, and have been genuinely justified, IS PRECISELY because I believe justification by Christ alone is TRUE, whatever they might think about it. Israel is justified by the imputed righteousness of the Messiah, and their misplaced faith in the Law doesn’t necessarily undo that.