What is the importance of the second coming of Jesus Christ?

from the old testament

• The concept of Jesus's second coming was a mystery to both Jews and Jesus's followers until He ascended into heaven after His crucifixion and resurrection. The Jews knew of the suffering Servant (Isaiah 53) and the conquering King, but they didn't understand that the work of the Servant and the work of the King would occur at two different times (Isaiah 7:14, 9:6–7; Zechariah 14:4).
• Zechariah 14:4 says that Jesus's feet will "stand on the Mount of Olives." When Jesus returns, He will fulfill prophecy, destroy His enemies (Zechariah 12:1–9; see Revelation 19:15-16), gather and bless His people (Isaiah 11:11; Zechariah 12:10), and reign as King (Isaiah 11).

from the new testament

• The "second coming" is the term used to refer to the future event when Jesus will return to earth, conquer His enemies, and reign as King of the world. Jesus described His return in Matthew 24:30: "Then will appear in heaven the sign of the Son of Man, and then all the tribes of the earth will mourn, and they will see the Son of Man coming on the clouds of heaven with power and great glory."
• People laid down their coats and palm branches for Jesus during His triumphal entry into Jerusalem because they expected a military leader to save them from Roman rule, as seen in John 12:13, "So they took branches of palm trees and went out to meet him, crying out, 'Hosanna! Blessed is he who comes in the name of the Lord, even the King of Israel!'" They were hoping for deliverance in the way they understood, not realizing Jesus came the first time to offer spiritual salvation, rather than political freedom.
• Even after Jesus's death and resurrection, the disciples didn't understand He had to leave and return (Acts 1:6–7). After Jesus ascended to heaven, the angels explained to the confused disciples, "Men of Galilee, why do you stand looking into heaven? This Jesus, who was taken up from you into heaven, will come in the same way as you saw him go into heaven" (Acts 1:11).
• People today still confuse Jesus's second coming with the rapture of the church, which occurs prior to the second coming. The rapture is described in I Thessalonians 4:16–17: "For the Lord himself will descend from heaven with a cry of command, with the voice of an archangel, and with the sound of the trumpet of God. And the dead in Christ will rise first. Then we who are alive, who are left, will be caught up together with them in the clouds to meet the Lord in the air, and so we will always be with the Lord." During the rapture, Jesus will collect His followers from the skies, but He will not set foot on the Earth; He will remain in the air.
• When Jesus comes again, He will come as a mighty warrior (Revelation 19). He will come to judge sin and evil and establish His reign as the "King of kings and Lord of lords" (Revelation 19:16). His second coming will be a display of divine power and authority, bringing justice and righteousness to the world (Revelation 19:11–16).

implications for today

While we can't know the exact timing of Jesus's second coming (Matthew 24:36; 2 Thessalonians 2:1–2), we are called to remain alert and recognize the signs (Matthew 24:4–29; Revelation 6–18). This awareness should encourage us to live faithfully, trusting in God's promises (Titus 2:13) and continuing to obey Him (Matthew 25:19–21). In our everyday lives, this means using our time, resources, and energy to serve God and invest in His kingdom and the things that will last for eternity. We are to stay focused on His promises, persevering in faith and living out His will with expectancy. Like the other prophecies about the end times, the promise of Jesus's return is to give us encouragement (Titus 2:13) and to exhort us to continue to trust and obey Him (Matthew 25:19–21) as we await His second coming.