Why is Lent Always 40 Days Long?
If we counted the days between Ash Wednesday and Easter Sunday, there would be 46 days.
So why is Lent only 40 days instead of 46 days?
In part, it's because of the significance of the number 40.
In the earliest days of Christianity, most of the Christians were Jews who celebrated the sabbath in the Temple and then celebrated the resurrection of Christ on the following day. That day was—and still is—the Lord’s Day, which is Sunday.
But Sunday isn't the sabbath.
Jesus died before sundown on what we now call Good Friday, before 3:00 pm. He then rested on the sabbath (from sundown Friday to sundown on Saturday) and rose from the dead on the third day (Sunday). This is why we say that "On the third day He rose again" (1 Corinthians 15:4 and the Apostles Creed) and not three days later, which would have been Monday.
We now call that particular Saturday, Holy Saturday, and we celebrate that Sunday as Easter Sunday.
We celebrate every Sunday as a mini-Easter, and Sunday is now the longest liturgical day of the week for Catholics because that day begins at sundown on Saturday and ends at midnight on Sunday. Monday is the shortest liturgical day because it doesn't begin at sundown on Sunday but just after midnight on Sunday.
The reason for this is that we celebrate Christ's conquering of death by dying and then rising from the dead, and opening the gates of Heaven which had been closed as a result of the Fall in Genesis 3.
This is why Sunday is the Lord's Day, because every Sunday we are celebrating the death and resurrection of Christ.
But why is Lent 40 days?
Numbers in the ancient world had symbolic meanings (this has nothing to do with modern numerology). Lent isn’t the only thing that’s associated with the number 40; it's also associated with:
Noah and the Flood
Moses in the Desert
Jesus Fasting in the Desert
A human baby in the womb
Noah: it rained for 40 days and nights and the earth was flooded; then a new creation came up out of the waters beginning when dry land first appeared.
Moses: spent 40 days on the mountain fasting and praying and then came down from the mountain with a new law; the 10 Commandments.
Jesus: fasted for 40 days and nights in the desert, and resisted the temptations of the Devil in the wilderness. He also spent 40 days with the Apostles after his Resurrection and then sent the Holy Spirit.
Human beings: exist for 40 weeks in the womb, and are then born into the world.
The number 40 is used in each of these examples as a mark of preparation to show us that God is preparing something amazing for us because He’s creating something new.
Noah and his family were separated from the evil that had filled the earth by the Ark, and the waters of the flood were a cleansing of that evil from the earth. Just as a new creation was “born” by the separation of the waters in Genesis 1, after the flood cleansed the earth, another new creation was born by coming out of the waters of the flood as they receded and dry land appeared.
On the Sabbath day, God called Moses out of the cloud on Mt Sinai and Moses then spent 40 days with Him. At the end of those 40 days, he was given the 10 Commandments (Exodus 24:16-18). These new laws replaced the extremely onerous old laws of the Egyptians that God’s people had been subject to during their time in Egypt. They became a new nation gathered together by God.
After Jesus fasted in the desert for 40 days in Luke 4:1-14, He resisted the temptations of the devil in the wilderness, and then taught in the synagogues so the people could glorify God.
He then referenced Isaiah’s announcement of the beginning of a Jubilee year (Luke 4:14-22), letting them know that the outpouring of forgiveness and mercy from God that is given during a Jubilee year was being fulfilled in that very year (verse 18).
(Luke 4:21-22): He said to them, “Today this scripture passage is fulfilled in your hearing.” And all spoke highly of him and were amazed at the gracious words that came from his mouth.
The Jubilee year was itself part of the preparation for the Descent of the Holy Spirit at Pentecost and the outpouring of God’s grace which strengthened the apostles and turned them from hiding out in the Upper Room in fear, to boldly proclaiming the Gospel in public.
The gestation period for human beings is 40 weeks. Sometimes babies are born early, but we can only say that the birth was early because we know that a human pregnancy should be 40 weeks. After those 40 weeks, we get to welcome that brand new and unrepeatable creation by God who has an immortal soul. Every human being is unique and unrepeatable (even identical twins have unique souls although they share the same DNA), and is created to become a citizen of Heaven at the end of its earthly life.
Lent is the time for us to remember that we weren’t made for this world, but for the next.
When we give up something for Lent, we give up things that we like so that we don't become overly attached to the good things in this world. Sometimes we take on extra practices like praying more, or performing particular actions as we try to develop a specific habit of goodness. Each of these helps us to put worldly things in their proper place instead of allowing ourselves to be controlled by them.
When God created the world, He proclaimed that it was good. At the end of each of the first 5 days of creation, Gen 1 says that “God saw that it was good.”
On the 6th day of creation, there’s a slight change. After God creates all of the animals and human beings, He says that it’s VERY good.
There is no 7th day in Genesis 1, because that was the eternal day where all of creation was in harmony and the human beings were united with God. That was what our relation to God was supposed to be like: to be with Him in perfect happiness with no suffering or death for human beings.
It’s in Genesis 2-3 that we see the Fall and separation from God, as well as His promise that He would fix that separation by sending a savior (Genesis 3:15).
That separation from God in Genesis 2-3 is a reminder of why we need a savior, why we sin, and why things in this world are imperfect and fall short of the Glory of God. The unity between God and all of creation in Genesis 1 and before the Fall in Genesis 2 is a hint of how things will be at the end of the world. There is so much imagery taken from chapters 1-3 of Genesis that is referenced in Revelation 19-21 (and in fairy tales!) because the end of the Bible is giving us an idea of what will happen at the end of the world; in particular how the perfection of life in Eden will be restored and elevated at the end of the world when God will make all things new.
Easter is our reminder of what God did for us so that we could enter through the gates of Heaven, and Lent is a help and reminder of how we prepare ourselves for that.