What does Matthew 3:16 mean?
Jesus, the Messiah, in His first recorded public appearance in Matthew, finds John the Baptist somewhere along the Jordan River and asks the prophet to baptize Him. John resists and then agrees to participate (Matthew 3:13–15). Some interpreters see this as the moment Jesus formally began His mission on earth, culminating in His sacrificial death for the sins of humanity, followed by resurrection and ascension Christian baptism certainly serves as a symbol of death, followed by resurrection: a new beginning.God the Father immediately responds to Jesus' baptism in a powerful way. As Jesus emerges from being fully immersed in the water of the Jordan River, the heavens are opened. Jesus sees God the Holy Spirit descending from heaven like a dove and coming to rest on Him.
It's unclear from this descriptions in the other Gospels whether only Jesus saw the heavens opened and the Spirit descend. This might have been witnessed by everyone present. Or, perhaps it was only perceived by Jesus and John (John 1:32). Luke does specify that the Holy Spirit took solid, bodily form (Luke 3:22). However, the phrase "like a dove" can either refer to the visual appearance of the Spirit, or to the manner in which the Spirit descended. As such, it's not explicitly clear that the Holy Spirit looked like a literal dove.
Regardless of such details, the Spirit coming to rest on Jesus served as a powerful confirmation that Jesus was being empowered by God. That confirmation is made even more explicit in the following verse.