Our Plea is Unity. Our Guide is the Bible
There is ONE calling by ONE Spirit into ONE body. ONE hope of the one calling
through ONE Lord, ONE faith, ONE baptism, which makes us children of the ONE GOD and Father of all, who is above all, through all and in all (Ephesians 4:17, 5:1), The ONE body is the Church (Eph 1:22, Col 1:18). Christ can have no more churches than he has bodies.

Can one scripturally say there is more than one church?
What does the Bible say? If the Bible is right, denominationalism is wrong. 

What must one do to be saved?

1. He must Hear and Believe the Gospel (Lk 11:28 an Jn 8:24),
2. Repent of Sins (Lk 13:3,5),
3. Confess Christ Publicly (Mt 10:32),
4. Be Baptized for the remission of Sins (Mk 16:16, Acts 2:38).
What must one do to stay saved? He must be faithful unto death (Rev 2:10)