In 1054, Pope Leo IX sent Cardinal Humber from Rome to Constantinople to bring the two halves of the Church together. Unfortunately the opposite happened when the cardinal excommunicated the Patriarch of Constantinople and the patriarch returned the favor to the cardinal. That's when things got bad and haven't been fully resolved since.
Why did the schism occur? Well, to our modern-day sensibilities, the reasons seem very minor. There were differences in opinion when it came to the Primacy of the Roman Pontiff. There were some differences in belief regarding the use of leavened vs. unleavened bread during the Eucharist. Throw in the mix the controversy surrounding the filioque clause, which is a controversy over whether we should say the Holy Spirit proceeds from the Father and Son, or just the Father, in the Nicene Creed.
These theological differences created a rift which ultimately created what is known as the Great Schism of 1054. Historians will say tensions were accumulating in the preceding centuries and that this schism was really a massive overreaction. Modern-day popes have all attempted, along with Eastern Patriarchs, to mend the schism and reunite these who parts of the Church. Partial reunions have resulted in what are known as Eastern Catholic Churches.
Now to the modern day, where there isn't a single schism in the Catholic Church resulting in two slightly different but very similar churches agreeing on 99% of issues. Now we have tens of thousands of Christian churches all over the world with wildly different beliefs. Instead of arguing over the use of leavened vs. unleavened bread, most Protestant churches do not even believe in the Real Presence. Instead of debating Petrine Primacy, or the status of Pope as First Among Equal Patriarchs, most Christian communities outright reject any form of papacy whatsoever.
Yet, despite these facts, for centuries, the Catholic Church has strove to convert the Eastern Orthodox Church back to the Catholic Church established by Our Lord. There was a desire for unity in belief and purpose. There has always been respect between the East and the West, but yet always an underlying desire for reunification.
Fast-forward to now. We hardly ever hear about conversion. We don't hear about missionaries entering into non-Catholic areas to will souls to Christ. We now speak mainly of dialogue and "deep respect" for other "religious traditions". This isn't just for Protestant denominations but other non-Christian religions.
I think this new approach is very problematic. Christ gave us a mission to baptize all nations in the name of the Father, and of the Son, and of the Holy Spirit. He did not say dialogue with other groups and just come to some kind of mutual respect. He told us to go out there and win converts. Of course, we are not the ones who do the converting, it's God himself.
To me, the new approach goes against the wishes of Jesus Christ who prayed that we be united as one, together. Furthermore, Our Lord tells us repeatedly that he is the way, the truth, and the life, and that no one comes to the Father except through him. Who are we to take all that Christ is saying and ignore it and tell him we know better.
I think all too often we see conversion as something negative, when it's only something positive. Our approach can certainly be negative, there is no doubt about that. We should meek, humble, and loving. Jesus himself said his followers should be recognized by their love. For this we must strive. However, at the same time, we cannot fall into a sense of indifferentism. It is a moral failing on our part to refuse to share the Gospel of Jesus Christ.
God's love for us is a gift, and God himself became incarnate to teach us the way to eternal life. Who are we to withhold this most incredible gift from others out of a misplaced sense of respect? In a secular sense it would be like finding out our friend had a winning lottery ticket worth millions of dollars but refused to tell him about it because we didn't want to disrupt him.
If we truly believe that Jesus Christ came to Earth to die for our sins so that we may be united more closely with him in this life and the next, it would be incredibly wrong for us to prevent others from knowing about this.
I think about this sometimes when thinking about the idea of conversion. Sometimes as devout Catholics, the question comes up of whether we should tell others of Christianity because by doing so they are held to a higher standard whereas before they would perhaps be living with invincible ignorance and thus lack moral culpability.
However, this is the wrong question. Again, back to the analogy of the million-dollar lottery ticket. Would we refuse to tell someone about the millions they won because maybe they'd have to make decisions as to how to spend it? To prevent them from being burdened, we simply do not let them know.
Of course this is not a great analogy as many people do actually suffer from winning the lottery. However, no one has ever been worse off for coming closer to Jesus Christ.
That's why I have issues with some of the language used in the modern world when it comes to other religions. I agree that we must have the utmost respect towards other people, and we should never address the traditions of others in a derogatory way. We must be kind and humble. But being kind, humble, and respectful does not mean fully consenting or agreeing with others. We have a mission, we have an incredible gift. Christ tells us about a peace that only he can give. Who are we to stop others from receiving the peace of Christ?
Let your light shine and do not hide it from the world. Bring the message of Christ to the whole world. They deserve to know Our Lord like you do.