Christians always agree on which doctrinal issues are essential and which issues are not.

Answer: No, they do not always agree.

The main doctrines that most Christians agree on are

(a) The deity of Jesus Christ, His virgin birth, and His sinlessness;

(b) The substitutionary atonement of Jesus Christ when e died on the cross;

(c) Salvation by grace apart from works;

(d) The presbytery or the structure of church government.

Doctrines that many Christians disagree on are

(a) The priesthood of believers (Christians);

(b) Speaking in tongues;

(c) Eschatology (doctrines about end times);

(d) God's promised future prosperity for Israel;

(e) The rapture, the order of resurrections, and the millennial reign of Christ on earth.