In listing three tangible ways I can personally improve relationships with Christians from other traditions, I cannot help but repeat two that have already been thoroughly addressed in this thread.
1. Attend worship services in churches of traditions different to my own.
2. Engage in respectful dialogue with Christians of other traditions, frequently asking questions about how and why they implement certain practices or emphasize certain beliefs.
However, I will also list a third avenue I have not yet seen mentioned in this thread:
3. Partner with Christian traditions indigenous to the community when evangelizing and ministering to that community.
As a Evangelical layman pursuing a vocation in missions, and having participated in several short-term mission trips, I have often thought about the prospect of Evangelicals partnering with native Christian traditions to more effectively bring the gospel to the surrounding culture. For example, on a recent trip to central Mexico, I could not help but notice the superstitious and syncretistic state to which Mexican Catholicism has degenerated.
I understand that orthodox Catholicism strictly differentiates between the veneration of religious images and saints and worship that is reserved for God alone; Mexican Catholicism does not make such a distinction. Prayer to and worship of statues of saints, especially Mary, is rampant, even with Teztelesque coin slots featured at the base of such statues in churches. Biblical literacy is nearly nonexistent, and the gospel of salvation through faith in Christ is largely unknown, instead replaced with functional Pelagianism and totemic superstition.
At the same time, I was moved by the beauty of the architecture and the cultural weight of the cathedrals that stand in the middle of every town square, their doors open at all hours for private worship and prayer. I have also been thoroughly impressed with the work of Bishop Robert Barron in reviving an evangelical and bibliocentric spirit in American Catholicism, while still emphasizing Catholic distinctives. Even if only nominally, Catholicism holds a cultural weight in Mexico that Evangelical Protestantism does not, and perhaps Bishop Barron’s ministry can use that cultural connection to reintroduce the gospel to Mexico.