How do we know baptism is immersion?

The practice of baptism as immersion is rooted in the definition of the Greek word 'baptizo,' which means to dip, immerse, or submerge. This is evident in scripture where significant biblical events, such as the baptism of the Ethiopian eunuch in Acts 8:38-39, illustrate immersion, as both Philip and the eunuch went down into the water. Furthermore, Jesus’ own baptism, described in Matthew 3:16, indicates immersion since He came up out of the water. This understanding is essential in affirming that true baptism must adhere to the form Jesus instituted, which is immersion, as it vividly represents the burial of the believer with Christ.