After rising from the dead, Jesus fully carried out the work God had given him. He had been entrusted with all authority in heaven and on earth (Matthew 28:18), and he exercised it decisively. Through his resurrection, his ministry, and the outpouring of the Holy Spirit, he conquered sin, death, and every opposition to God's will (1 Corinthians 15:25-26). The powers that had once stood against God—empires, authorities, even spiritual forces—were judged and subdued during the first century, culminating in the destruction of Jerusalem in 70 AD (Luke 21:20-22; Matthew 24:34). In this sense, the "enemies under his feet" were already dealt with in that era.
From approximately 66 AD to 70 AD, a period marked by turmoil, war, and the fall of Jerusalem, early believers understood these events as the fulfillment of Jesus' prophecies about his coming in judgment—what many refer to as the Second Coming. During this time, Jesus' authority and kingdom were fully revealed as the old covenant world passed away and the new covenant order was firmly established.
Once everything was put under his authority, Jesus handed the kingdom back to God the Father (1 Corinthians 15:24). His reign had been temporary and purposeful, a divine stewardship to accomplish God's plan on earth. The New Testament portrays this not as a future event but as something realized: Christ now reigns no longer as a temporal king, but as the fully victorious Son who submits to the Father, making God "all in all" (1 Corinthians 15:28). The work of salvation, judgment, and establishing God's justice was completed in that generation, fulfilling the promises Jesus spoke of while on earth (John 17:4-5).
In this story, humanity experienced the fullness of Jesus' reign spiritually and historically. The temple, the old covenant system, and the old authorities were no longer necessary; they had served their purpose. Jesus' victory was complete, and he returned the kingdom to the Father, establishing God's ultimate authority fully on earth. Now, from the perspective of history and scripture, we live in the era after the Son has completed his reign, where God's plan has already been enacted, and all things have been brought under His authority as intended.