The Three Remembrances
This parsha is known for the tochecha, the harsh words of rebuke G‑d delivered to the Jewish people, in which the most exacting punishments associated with Galus-exile are threatened.
Near the end of the very harsh words of rebuke, the Torah inserts G‑d’s promise that He will remember us and take us out of exile.
“I will remember My covenant with Jacob and also My covenant with Isaac and also My covenant with Abraham I will remember, and I will remember the land.”
It is axiomatic that the Torah is frugal with its words. If the Torah can express a thought in fewer words it will do so. Every added word must contribute a new layer of meaning and a novel message which we would not have derived from the passage had that word not been inserted.
What then, commentators ask, does the Torah want to convey to us by adding the words “and also with My covenant with Isaac” and then it repeats this phrase, “and also My covenant with Abraham?” It could just as well have written, “I will remember My covenant with Jacob, Isaac and Abraham…”
Another question, why does the Torah mention the Patriarchs in reverse order? Shouldn’t it have mentioned them in chronological order as Abraham, Isaac and then Jacob?
Rashi answers this question by stating:
“Jacob, the youngest, is sufficient for this, but if he is not sufficient, Isaac is with him, and if he is not sufficient, behold Abraham is with him for he is sufficient.”
But Rashi’s answer needs further clarification. Why would G‑d have a doubt  whether Jacob’s merit was sufficient?
The Short Answer
The short answer to this question is that Galus conditions can manifest themselves in several ways. If the spiritual conditions of Galus are relatively mild, then only the power of Jacob would be necessary.  If however, Galus becomes more spiritually oppressive, we will then have to rely on both Jacob and Isaac for salvation. And if Galus conditions deteriorate and reach their nadir, we will then have to invoke the inspiration and power of all three Patriarchs.   
Each of the Patriarchs serves as a role model to help us overcome the most serious challenges that confront us in exile. Moreover, their souls are the sources of our souls. They are therefore not just sources of inspiration for us but they actually empower our souls to break out of the paralyzing forces of exile.
However, the three Patriarchs were not monolithic. Each of them possessed a unique dominant trait which they bequeathed to their children. 
Thus the Torah tells us that if we suffer from a lack in one specific dimension, which landed us in Galus-exile and kept us there, Jacob’s merit will stand us in good stead because he met that challenge and bequeathed to us the potential to do the same.
In other words, if Galus was caused by certain lapses in our personalities we are empowered to deal with them by virtue of Jacob’s legacy to us. But if our challenge is compounded with other more adverse liabilities we will need the power of Isaac together with that of Jacob. And if our challenge is further compounded by a third hurdle of a different and more serious nature, we will then need the combined energy of Abraham, Isaac and Jacob.
What are these three situations and how do Jacob, Isaac and Abraham address them, in that order?
Jacob’s Power to Get Us out of Galus
Let us begin with Jacob.
Jacob, our Sages tell us, personified the attribute of emes-truth, or, more precisely the trait of consistency. Jacob is described in the Torah as an “Ish tam yoshev ohalim-an honest person, dwelling in tents.”
Because truth and sincerity were his strengths, he was challenged by his dealings with his brother Esau and his uncle Lavan, both of whom possessed the diametrically opposite traits of deception and insincerity.
Esau, we are told, deceived his father about his low spiritual state, acting piously in Isaac’s presence but committing the most heinous crimes in private. Lavan was known as a schemer. He deceived Jacob from the get-go, when he tricked him into marrying Leah instead of Rachel. Jacob escaped the clutches of both brother and uncle, remaining faithful to his attachment to G‑d.
The challenges that Jacob had to deal with, falsehood and inconsistency is the challenge of Galus. Galus, by definition, is a state of mind in which there is no consistency. Galus itself is only a temporary period between the era of the Second Bais Hamikdash and the third, which will be built soon by Moshiach. Galus has been compared to a dream in which we can experience opposite events, going from one place and experience to a totally foreign one. Galus preoccupies us with the temporal. One who is deeply inspired during events such as prayer and Torah study can, a minute later, become totally engrossed in far less edifying and uplifting matters.
This is the most benign form of exile.  When we are engaged in prayer and other spiritual pursuits, at least in these moments, we are in the right place and situated above the darkness and concealment of exile.
Isaac Gets us out of Galus Stage Two
But Galus can get even more problematic. In addition to the ephemeral aspect of Galus, it can also be characterized by its superficiality.
This aspect of Galus manifests itself in several ways. One form is the way we look at others and see only that person’s surface. With that myopic view we tend to judge others unfairly, not being able to see who they really are beneath the façade.
In terms of our relationship with G‑d, this superficial Galus approach affects the way we pray. Frequently, even while we are praying and removed temporarily from the mundane world, our perception of and feelings for G‑d are shallow. This is due to the obstructive power of Galus that does not allow us to see beneath the surface.
This Galus characteristic is more serious than the former one. The problem with inconsistency is offset at least by the time we are involved in a positive pursuit. While we are praying, our hearts and minds are in the right place.
However, with inconsistency augmented with superficiality suggests that we are actually never in the right place. This is a deeper and more serious form of Galus.
Isaac’s Contribution to Getting out of Exile
The trait of Jacob does not suffice to deal with this added challenge. We need to avail ourselves of the power bequeathed to us by Isaac.
Isaac personified the attribute of gevurah-penetrating judgment, which pierces through the veneer.
Isaac was known as a well-digger. In addition to its literal meaning, it is a metaphor for his ability to drill beneath the surface of others and see their true inner virtue. This explains the enigmatic story of his desire to bless Esau. Isaac must have known that Esau’s behavior was far from ideal. Yet Isaac chose to bless him because, as the Kabbalists teach, he saw powerful spiritual sparks in Esau’s core. Isaac thought that he could help Esau actualize these positive forces through the blessings. It takes an Isaac-personality to see the good and Divine in everyone and everything.
When temporality and inconsistency, or the lack of emes, are compounded with superficiality we need both Jacob and Isaac to come to the rescue. While Jacob instills the trait of emes in our souls, Isaac is the one who inspires and enables us to dig deeper into others’ psyches and see their hidden good.
The Bottom of Galus Corrected by Abraham
Galus conditions can deteriorate even further, to the point where we become desensitized. Even superficial elements of love, compassion, concern and reverence, among other traits, elude us, the pain, suffering, alienation and oppression we have experienced in exile have desensitized us.  We have become self-absorbed. As a result, in addition to Galus inconsistency and superficiality we may also suffer from Galus narcissism.
To extricate ourselves from this new scourge, we must avail ourselves of Abraham’s spiritual power that he bequeathed to us, in addition to the inspiration of Jacob and Isaac.
Abraham has the ability to do this because he personified the attributes of love and kindness and empowered us to break out of the self-centered influences of Galus.
How do we tap into these three traits that we inherited from our Patriarchs?
Remembering the Land
The answer lies in the end of the verse:
“…and I will remember the land.”
The Zohar states that the land is a metaphor for King David, the progenitor of Moshiach.
This means that the way to actualize our spiritual potential is to recognize the centrality of Moshiach in our lives. We must never take our minds and hearts off our anticipation for and welcoming of Moshiach. We must persistently beseech G‑d to bring Moshiach to take us out of Galus and return us to our Promised Land; return in the full sense of the word—both physically and spiritually with the building of the Third Bais Hamikdash.
When that happens, we will discover that we are indeed capable of breaking out of our ego-driven lives, discovering the deepest layers of our souls and of G‑d.  We will experience all of this with profound sincerity and consistency; the traits of Jacob, Isaac and Abraham, respectively!