Just because I was obedient to God yesterday does not mean that I will be obedient today. Each day stands on its own. If I was obedient to Him yesterday, good. But if I am disobedient today, then yesterday’s obedience will not help me. On the other hand, if I was disobedient yesterday, I can change course and be obedient today. Each day is its own significant sliver of a lifetime.
Some people think that because they obeyed God at some time in the past that somehow that obedience will serve them today. Thus someone thinks to himself, “I used to live a bad life but I turned it around when I was 30; therefore God will continue blessing me for that when I’m 40, 50, 60, and more.” This not only trivializes God, it trivializes our lives. Each of us have moral decisions to make every day: some big, some small. But every day. God judges us for these choices. Good choices bring His blessings; sin brings His wrath. Each human life is important. Each day of each human life is important.
For this reason Jesus said, “Don’t worry about tomorrow; each day has enough trouble of its own.”
Everyone is going to heaven, but the course of our life between now and then is determined by how righteously we live each day between now and then.