Final answer:
The church expresses her unity through charitable works, sacraments such as the Eucharist and Baptism, a hierarchical structure of clergy, monastic lives, and shared doctrines like the Holy Trinity and the Ten Commandments.
Step-by-step explanation:
The church expresses her unity in various ways, reflecting both her rich traditions and diverse practices. Christians often demonstrate their unity through charitable works, such as creating religious art or engaging in acts of mercy and service. Examples include the breathtaking frescoes by Giotto in the Arena Chapel.
Rituals or sacraments are another way unity is expressed; partaking of the Eucharist during Mass or through the sacrament of Baptism connects believers in profound spiritual communion. The hierarchical structure of traditional Christian churches, with ordained clergy at different levels, also underscores the church's unity through a shared authority and order.
Additionally, individuals sometimes choose a life of devotion as nuns or monks, which is another expression of unity through a common and cloistered life of prayer in a monastery. Importantly, the spectrum of Christian belief includes nontrinitarian Christians who share in the broader Christian unity while maintaining distinct theological views.
Lastly, shared doctrines such as belief in the Holy Trinity and adherence to the Ten Commandments also bring Christians together, despite variations between different Christian groups in their sacred texts, such as the inclusion of the Apocrypha in the Catholic Bible or the Book of Mormon in Latter-day Saint tradition.