Bo - Looking Up

When Hashem explains to Moshe and Aharon about the 10th plague, he tells them to convey to the Jewish people the proper way to be prepared for this plague.

And they shall take [some] of the blood and put it on the TWO DOORPOSTS and ON THE LINTEL, on the houses in which they will eat it.

Shmot 12:7

Yet when Moshe calls the elders together to actually explain to them what Hashem had told him. Moshe says this over slightly different.

And you shall take a bunch of hyssop and immerse [it] in the blood that is in the basin, and you shall extend TO THE LINTEL and TO THE TWO DOORPOSTS the blood that is in the basin, and you shall not go out, any man from the entrance of his house until morning.

Shmot 12:22

In presenting the instructions for the Jewish people to carry out, Moshe changes the order for how the blood should be applied to the doorway.

Order
Says the Baal HaTurim in regards to the change of order from the earlier verse to Moshe's version, he explains this as showing that the order really doesn't matter. No matter which order you put the blood on the doorway, you will have fulfilled your obligation.

Symbol of the Doorway
Says the Kli Yakar, by way of Midrash, we can see the deeper meaning in all the elements of the doorway. As the midrash Eicha Rabbah relates, this is like HaKodesh Baruch Hu appealing to the Jewish people.

From the days of your fathers you have departed from My laws and have not kept [them]. "Return to Me, and I will return to you," said the Lord of Hosts, but you said, "With what have we to return?"

Malachi 3:7

And the midrash continues, saying, "...rather You should return first." The midrash rests upon the following verse:

Restore us to You, O Lord, that we may be restored! Renew our days as of old.

Eicha 5:21

The Kli Yakar establishes that from the point of view of the Jewish people, Hashem provides the power and strength to change our ways, and come back to him.

The Lintel
Based on this interpretation, the Lintel, the singular element in the doorway, serves to represent Hashem, positioned across the top. This is found the following verses.

For He has looked down from His holy HEIGHT; the Lord LOOKED FROM HEAVEN to earth,

Tehillim 102:20

The Doorposts
The two doorposts literally support the lintel, across the top. The lintel symbolizes Hashem looking down, so who supports Hashem? The merit of the Patriarchs and Matriarchs. We see this in the verse:

which are the abode for the God Who precedes all, and BELOW ARE THE MIGHTY ONES OF THE WORLD. He expelled the enemy from before you, and said, 'Destroy!'

Dvarim 33:27

Who are the mighty ones of the world, who is deserving of this accolade? The Patriarchs are part of the infrastructure that form the foundations for Judaism, and our relationship with Hashem. That is why when Hashem gives over the instructions to Moshe, He imparts honor to the Patriarchs and lists The Doorposts before the Lintel. That is to say that righteous ones, they are the Patriarchs and the Matriarchs.

The Source of Power

However Moshe changed the order. Why? This goes along with what the verse says in Malachi. At this stage of the Exodus, the Jewish people are at their weakest - spiritually and physically. Moshe turns his pleas heavenwards, engaging Hashem to impart strength to the Jewish people.

The Divine Relationship

Continues the Kli Yakar, saying, this helps to explain the Rashi in Shir HaShirim.

How fair are your feet in sandals, O daughter of nobles! The curves of your thighs are like jewels, the handiwork of a CRAFTSMAN.

Shir HaShirim 7:2

Says Rashi on the word "craftsman":

The Hebrew word for "craftsman" is "אוּמָן"  which is like the word "אֳמָן". We say the word  "אֳמָן" in order to show praise of the Holy One, blessed be He, the Israelites praise Him from TOP to BOTTOM. They commence, so to speak, from “His head is as finest gold,” and progressively descend to “His legs are as pillars of marble,” since they come to appease Him, to draw DOWN His Shechinah from the HEAVENLY ABODES to the EARTHLY ABODES. He, however, counts their praises from BOTTOM to TOP: “How fair are your feet!” and He progressively counts until, “Your head upon you is like Carmel,” until He comes to draw them to Him.

 The Jewish people  relate to Hashem from the heights down to our level, looking up to gain strength. While Hashem relates to the Jewish people from the lowest to high, bringing the Jewish people up to Him.

That is why Hashem instructs Moshe to start with the doorposts and then the lintel, for Hashem to show that His glory starts from where the Jewish People are and rises up to Him. The righteous add power and heroism   to the heights.

Likewise, in respect to Hashem, Moshe precedes the lintel to the doorposts, to show that for us the glory comes down to us from above.