It’s not manipulative or insensitive to bring up the urgent nature of salvation. It’s simply the truth. The time of opportunity will end.
As Christians, we’ve come alive to the truth that history isn’t cyclical, always repeating in an endless rotation of events, spinning till any given part of it becomes meaningless. No! We know that God has created this world, and that he will bring it to a close at the judgment. We know that he gives us life, and he takes it away. The time that we have is limited; the amount is uncertain, but the use of it is up to us. So Paul tells us in Ephesians to “make the most of every opportunity (5:16).”
Like a collector buying up a collection, we should desire to capture each fleeting hour and to turn it into a trophy for God and his grace. As Paul said, “The time is short. From now on … those who use the things of the world [should use them] as if not engrossed in them. For this world in its present form is passing away” (1 Cor. 7:29, 31).
What are your circumstances right now? Trust the Lord to use you in them instead of seeking for new ones. Don’t let the passing permanence of your world or the lulling tedium of certain long hours and minutes make a fool of you. The days are “evil” (Eph. 5:16) in the sense that they are dangerous and fleeting, and we must redeem the time and make the most of every hour. So we say with Paul that, in view of a certain judgment, Christ’s love compels us to tell the good news to others (see 2 Cor. 5:10–15). We must be honest not only about the cost of repentance, but also about the expiration date of the offer. Such honesty compels us to urgency.
Mark Dever, The Gospel and Personal Evangelism, 58-59