The concept of posterity is similar to descendancy. When you think of someone's posterity you think of their name and legacy surviving for as many future generations as possible. It leads to the question of why someone would be so concerned about their posterity when they will themselves one day be dead and not see it? For so many people, the concepts of legacy and posterity are a continual taunt in their life. They will put all their effort into something that they will never themselves hold. In that way, it can be a putrid posterity.
When Abimelech came to Abraham to seek peace between them at Beersheba, his ultimate purpose was to protect his posterity. Genesis 21:23 Now therefore swear to me here by God that you will not deal falsely with me or with my descendants or with my posterity, but as I have dealt kindly with you, so you will deal with me and with the land where you have sojourned. Why was Abimelech so concerned to protect something that only has true value in a future he will never inhabit? Why is it that so many humans are so concerned with something of themselves increasing beyond their graves? The author of Ecclesiastes gives us a beautifully eloquent answer.
Ecclesiastes 3:11 He has made everything beautiful in its time. Also, he has put eternity into man's heart, yet so that he cannot find out what God has done from the beginning to the end. The reason humans are restrained from the full extent of our temporal self-centeredness is partly due to the fact that God has put eternity into our hearts. We are forced to desire beyond our own immediate life. We are forced (whether we admit it or not) to think of life beyond the grave.
A few years ago I was in the Chicago Museum of Art with my son, Dave. He is a very talented artist. I was walking around the wall of paintings and standing about 4-6 feet from each painting. I then came across this huge painting with big broad-brush strokes. It intrigued me and I stopped and moved close to wonder why this painter had used such big strokes. Dave came to me and asked, “Dad, what are you doing?” I answered, “Why did this artist use such a big brush?” Dave replied, "The artist doesn’t want you to stand this close." He grabbed me by the arm and took me right out to the center of the room. “That’s what the artist wants you to see.” It was a beautiful portrait.
That’s what It’s like for us. How can we possibly understand purpose in our single earthly life if this is all there is. How can we satisfy the desire of eternity in our heart by looking only at our finite self. To see and experience the true wonder of eternity, we must know it from the only One who can give eternal life. If we are in Christ, one day we are going to see the entire painting and say, “Masterpiece.” If we are not in Christ, the eternity in our heart will never be satisfied.
The eternity in the heart of Abimelech motivated him to make a treaty with Abraham so that his line of descendants would be kept safe and his name continue beyond his own grave. Sadly for Abimelech he was blind to God's eternal hope standing in front of him in the life of Abraham and Isaac.
Christians must be careful as we also consider eternity. While a good name and a legacy of the gospel can be admirable, sometimes we can seek for our own name and even our own ministry to be our focus of eternity rather than our desire for Christ's name to have eternal glory. We can too easily take our eyes off Christ and exchange simple faithfulness to the glory of Christ for our own ministry or family empires to be ongoing promotions of our own name. Christians can also take our eyes off the purpose of eternity and see a putrid posterity.
The big picture is always God's picture and to be part of that picture it always means that Christ and his glory alone is our goal. The greatest eternity in our hearts that there can ever be is the eternal dwelling presence of Christ with us - to live with God and enjoy his glory forevermore.
Stand back and look at the big painting.
You'll see that the eternal glory is not a painting of you.