The Catholic Church has been trying to destroy the true ekklesia since the fourth century. Who did you think they have trying to silence all those years?
The early fights were with heresies such as: Gnosticism, Arianism,, Monophysitism, Nestorianism, Monarchianism, Docetism, Apollinarism, Monothelitism, Antinomianism, Adoptionism, Sabellianism, and more.
You’re not claiming one of these as your non-denominational Christian consistent since the time of Christ are you?
If not, who specifically are you referring to then? Fourth century, fifth, sixth...?