Death is certain. Can a person die before his time?
It is not unusual to hear someone say, "It was his time to die." Or, "He didn't die before his time."
The question: "Can a man die before his time? In a sense this question is complicated to answer. However, to realize that God knows all things, before the beginning, after the ending and before the beginning and ending provides insight into the answer to this question. It is true that God knows when any person and every person will die. He is the "Alpha and Omega, the beginning and the ending." God is Infinite, man is finite.
Many of the promises of God are conditional, i.e., on the condition of what response a man makes to God's promises. An example of the part man has in deteriming the effects on him of God's promises is revealed in the commandment, "Honor your father and mother" --- which is the first commandment with promise --- so that you may enjoy long life on the earth." (Exodus 20:12-3 and Ephesians 6:2-3 NIV)
The inference is clear, a failure to honor your father and mother may lessen your enjoyiment and shorten your days of life.
Can a person die before his time? The answer is yes and no...that depends. What about the person who dies before he is able to choose? What about the person who dies as a result of the choices he makes? What is true for both is they die at their appointed times, the former without making a choice and the latter, likely, as a result of making a choice or choices. His choices may have played a role in his death date.
A warning! Be careful as to how you assume or declare that a person died because it was his time, without realizing that he may have died before his time had he made choices that would have prolonged his life. He may have died because he pursued destructiveness rather than health. The person may have had the opportunity to chose a better way to live that would have extended his days or years on earth than the one he chose.
To reiterate, many of God's promises or conditional. They require a person to respond positively rather than negatively to obtain the promised good. God always keeps his promises.
Living today the best you can, doing all the good you can and being your own best friend are the keys to full life, hence a good death at the appointed time.