As a Christian I know to disregard such talk even when it comes from misguided Christians.
Christians believe that there will be a day when the risen Jesus Christ will return to finally and fully establish His kingdom. The old creation will be brought to an end and Christ's new creation will bloom to full flower. Preparation for that day is, in fact, a key theme of the Advent season we celebrate before Christmas, a season that starts on December 25.
But we have it from Jesus Himself that speculation about when it will happen is pointless. Jesus says: "...about that day or hour no one knows, neither the angels in heaven, nor the Son [Jesus Himself, God the Son], but only [God] the Father" (Mark 13:32).
This statement is mysterious on several levels, of course. Christians believe that God has revealed Himself to be one God in three Persons. The New Testament speaks of God the Father, God the Son, and God the Holy Spirit and Christians have come to use the shorthand term, the Trinity, to describe God's three-in-oneness. But in the words above, Jesus seems to be saying that there are some aspects of their work that each Person of the Trinity keeps to Himself.
Be that as it may, there is no mystery about Jesus' fundamental point, which is that to speculate about when this world will come to an end is pointless. That day is shrouded in a mystery we're not meant to know.
In the meantime, Jesus goes on to say, we have work to do. "Beware, keep alert," Jesus says, "for you do not know when the time will come...Keep awake!" (Mark 13:33-37)
- *To entrust ourselves--including our past sins, our present decisions, and our future destiny--to Jesus Christ alone. "This is the work of God," Jesus says, "that you believe in Him Whom He has sent" (John 6:29). Jesus is the One sent by God the Father (cf. John 3:16-18)
- *To use our talents and gifts in ways that are productive, expressing love for God and love for others, including our families, and that glorify the One Who gives us our gifts. (Romans 12:1-2)
- *To tell others about God becoming one of us in Jesus, Who died, taking the punishment for sin we deserve, and rose again in order to open up new, everlasting life with God to all who turn from sin and believe in Him. (Matthew 28:19-20)