The Christians who think they're "spiritual Israel" like to take a verse like Paul saying in Philippians that "we are the circumcision" (Philippians 3:3), misinterpret it as literal rather than metaphoric (it's a simple metaphor), and fancy themselves as those who will now fulfill God's literal promises to
the literal nation Israel.
Oops. They're wrong again. Rather than being the faithful Israel of their own whimsical fancy, Christians are actually the modern-day representatives of why God divorced this nation in the first place: confidence in flesh.
Here's the real truth on Philippians 3:1-3.