Final answer:
The Passion, death, Resurrection, and Ascension of Jesus are celebrated during the Easter Triduum and Easter season, culminating in the observance of his Ascension forty days after Easter.
Step-by-step explanation:
We celebrate Jesus' passion, death, Resurrection, and ascension when we celebrate the Easter Triduum and Easter season. This period begins with Maundy Thursday, commemorating the Last Supper and Jesus' washing of the Apostles' feet, continues with Good Friday, when the Passion and death of Jesus are observed, and reaches its peak on Easter Sunday, celebrating the Resurrection of Jesus. The Ascension of Jesus is usually observed on the fortieth day after Easter.
Thus, the Easter season encapsulates all these events, starting from Jesus' final days, through his death, followed by his triumph over death and conclusion with his return to heaven. These events are the cornerstone of Christian belief, emphasizing Jesus as the messiah and savior, who fulfilled prophecies and brought salvation through his sacrifice and victory over death, resonates deeply in Christian theology and art.