Fallenness
Verses 4–11 speak about the second fact of reality regarding the human condition. We are fallen. We sin. We do evil and evil is done to us. We are guilty before God:

For we are brought to an end by your anger; by your wrath we are dismayed.
You have set our iniquities before you, our secret sins in the light of your presence.

For all our days pass away under your wrath; we bring our years to an end like a sigh.
The years of our life are seventy, or even by reason of strength eighty; yet their span is  but toil and trouble; they are soon gone, and we fly away.

Who considers the power of your anger, and your wrath according to the fear of you?

Psalm 90 is very blunt about the sinfulness of the human condition. Despite the many blessings of this life, the reality of evil and suffering due to sin indicates that the world is out of order. Things do not often work well or as planned. Everything, animate and inanimate, degrades and degenerates. We age and die. Death is our destiny.

Also, human relationships are out of order. A few moments watching the evening news, reading the headlines, talking with our neighbor or simply a moment of existential honestly in front of the mirror informs us that sin produces sadness and loss in our lives. So, let’s make several observations based on these verses.

Verse 8 says: “You have set our iniquities before you, our secret sins in the light of your presence.” This tells us two important facts. First, we are morally accountable to God. He is not only our creator but also our judge. Second, God knows everything about us and we cannot hide anything. We must give account for everything we do, think, and say.

Verses 9 and 10 say: “For all our days pass away under your wrath; we bring our years to an end like a sigh. The years of our life are seventy, or even by reason of strength eighty; yet their span is but toil and trouble; they are soon gone, and we fly away.”

Thomas Hobbes, 17th century British philosopher, described social relations among human beings as “continual fear and danger of violent death; and the life of man, solitary, poor, nasty, brutish, and short.” This results in a “state of war” whereby “every man is enemy to every man.” Hobbes describes much later in human history what Genesis 4–11 ascribes to mankind immediately after the fall. The human heart, alienated from God and from one another, became “only evil all the time” (6:5).

Prayer For Wisdom
In light of all that Psalm 90 tells us, the only valid response for the Christian believer is Moses’ simple prayer: “So teach us to number our days that we may get a heart of wisdom” (v. 12). Given the facts of reality, the wise posture is one of listening and learning. The petition for God to teach us indicates submission, obedience, and accountability.

Moses asked God to “number” his days. This means that he understood his frailty and sin. So should we. We must recognize that our every breath is a gift. We should realize that we are stewards of our existence, who must give account for our lives. Also, to “number our days” is to invest ourselves in what really matters and what has eternal significance. We then strive to be good stewards over our “heart, soul, mind, and strength” (Mark 12:30).

Finally, Moses wanted God to give him wisdom. (See Psalm 39:4–6.)  God gave Moses a heavenly perspective about the human condition. With this as his North Star he was able to use his spiritual compass to navigate the world in a way that pleased his creator, Lord, and savior.

We should desire this wisdom as well.

Thank God, we have the scriptures “which are able to make [us] wise for salvation through faith in Christ Jesus” (2 Tim 3:15). He has  “become for us wisdom from God—that is, our righteousness, holiness and redemption” (1 Cor 1:30).