Final answer:
Jesus was anointed by the Holy Spirit during His baptism in the Jordan River, which marked the beginning of His public ministry and His mission of salvation.
Step-by-step explanation:
Jesus was anointed by the Holy Spirit at His baptism, which is recounted in the Gospels of Matthew, Mark, and Luke. The Baptism of Christ is commemorated in the Eastern Orthodox Church on January 6. At this event, John the Baptist baptizes Jesus in the Jordan River and the Holy Spirit descends upon Jesus in the form of a dove. This anointing signifies the start of Jesus's public ministry and his work of salvation.
The anointing of Jesus is a significant event because many Christians believe it highlights when Jesus was empowered by the Holy Spirit to embark on His mission for humanity's salvation. The person of Jesus is seen as sacred and holy from the time of his baptism by the Holy Spirit. This event does not only hold theological importance but also influences the practices of Christian baptism in many traditions, which are seen as reflections of Christ's own baptism.