Bodies are composed of many members with differing functions (1 Corinthians 12; Romans 12), and this is true of the Lord’s body—the church—as well (Colossians 1:18). Ephesians 4:11 states that some were given as apostles, some as prophets, some as evangelists and some as pastors. No one alive today meets the qualifications to be an apostle (Acts 1:21ff), and prophesy was a miraculous gift of the 1st century and as such is no longer present. (Only apostles could pass on the miraculous gifts, Acts 8:18). This leaves us with evangelists and pastors. The evangelist is the one who proclaims the Gospel, and pastors are the ones more commonly known as elders (Acts 20:17, also known in Scripture as shepherds or pastors, Acts 20:28; 1 Peter 5:2).
Deacons are important to the body as well, but their task is a different one. According to their establishment in Acts 6, their purpose is to meet physical needs while the leadership focuses on the spiritual needs. This doesn’t make one role more important than another, just like one part of your body is not more important than another. What this means is that for bodies to function properly, the different members need to be present and working together to bring glory to the Head—Jesus.