Although our time on earth may seem sometimes like a long hard slog, it is nothing compared to the endless eternity we will spend either in heaven, if we are a true believer, or otherwise in the eternal lake of fire. The reality is

Although life is short, focus on eternity

those who indulge in the so-called pleasures of sin even for their whole earthly existence will regret it forever, while “our light and momentary troubles are achieving for us an eternal glory that far outweighs them all” (2 Cor 4:17). Mankind is like a flower that springs up, then quickly fades away for our life is like a vapour that appears for a short time then vanishes (Job 14:1,2; Jas 4:14). However the consequences of our choice to either accept or reject the offer of salvation last forever (Jn 3:16,36; 1 Jn 2:17). No excuses will be permitted and there is no opportunity for a second chance for  those who die without knowing Jesus as Saviour to swop sides.

"Show me, O Lord, my life's end...let me know how fleeting is my life...Teach me to use wisely all the time I have" (Ps 39:4, 90:10,12). Humanity generally has little appreciation of the life, hereafter (the heaven to gain and the hell to shun). Instead the sole focus is on the struggle to acquire what isn't needed and what won't be enjoyed for long (Ps 39:5,6; Lk 12:15-21). Time is passing, and I am passing out of time. In the time the Lord has allotted us on earth (only He knows how much that will be) we should be focused on loving Him with all our being and ensure we are fulfilling His calling on our lives (Job 14:5; Ps 139:16; Mk 12:30; Phil 3:12). Do I take seriously the task God has assigned me or do I need a reminder, "See to it that you complete the work you have received in the Lord" (Col 4:17). The Bible states after death we will give account to God how we lived on earth will this be a time of commendation or embarrassment because we have squandered the time and resources He gave us (Heb 9:27)?

Jesus and Paul both stated they had finished the work God had given them to do (Jn 17:4, 19:30; 2 Tim 4:7). 

See also: call/calling, death, perspective, time/timing.