I will add that you can ‘find’ the church age as well as the millennial kingdom throughout the Old Testament - but those truths need the New Testament to shed light upon them - as Paul elucidates them as revealed mysteries.
The New is in the Old concealed . . .
The Old is in the New revealed.
OK. How would this fit in?
“Unto him be glory in the church by Christ Jesus throughout all ages, world without end. Amen.” — Eph 3:21