The Eastern Orthodox reject Catholicism. Are they guilty of rejecting Christ? Perhaps you don't understand this but "the church" is made up of ALL the redeemed followers of Christ, those who have received the gift of God which is eternal life through faith in Jesus Christ. If someone rejects Catholicism, they aren't rejecting "the church", just a particular church which asserts IT is the church that Christ founded.
Now, I don't deny that there ARE real Christians that are Catholic, just that the Roman Catholic church is NOT the church spoken of in Scripture. There are many tenets of the Christian faith that Catholicism still holds to, of course, and there are many godly, genuine and sincere Christians that worship in that manner. But, genuine, godly, faithful Christians also exist outside of the Roman Catholic church which demonstrates that there ARE Christians who are not Roman Catholic and they also are part of THE church Jesus established, just as there were in the early centuries of Christianity. Once this important distinction is realized, pride, animosity and hatred can be alleviated.
no they don't
Catholics have never denied that...of course there are Christians outside the Catholic church...but all of the myriad of protestant denominations are in some way incomplete of full Christianity. One of the most important, if not THE most important belief in Catholicism is the true presence, in the Eucharist, of the Body, Blood, Soul, and divinity of our Lord Jesus Christ...He said it was there and we believe it.