Yaakov Avinu says I conquered the Emori with my חרבי וקשתי my sword and bow. Rashi explains the words of Chazal to be my wisdom and tefillah. The bow symbolizes tefillah the power of dibbur. The Maharal explains that it is the arrow of the bow that correlates to tefilla. An arrow can kill from a distance so can one’s tongue if one speaks Lashon HaraTefillah is likened to the arrow it also has the power to ascend a great distance to shamayim and reach the Kisay Hakavod. However this interpretation makes the arrow the symbol of tefillah, while the passuk describes the tefillah as a bow?
Therefore we suggest that the bow is also part of tefillah for the more one pulls the string of the bow towards his heart the greater the distance it will go. Tefilla is called the avodah of the heart. If one merely davens with his body, moves his lips, shukles, and is distracted causing the absence of kavanah, then it is tantamount to placing tefillin on your leg. You’ve got the wrong limb and there is no mitzvah fulfillment.

How can we have the proper kavanah? It is by connecting to the Avos, since they were the individuals who composed the three tefillos the avodah of the heart. The Sfas Emes וארא תרסא writes the following about the hearts of the Avos.
ובאמת זה תכלית שלימות בנ”י שיתמשכו אחר לב האבות כדכתיב והשיב לב אבות על בנים ולב בנים על אבותם ואז יהי’ הגאולה במהרה בימינו. כי האבות היה להם רק לב אחד לאביהם שבשמים ולא הסיחו דעת מאהבת ודביקות הבורא אפילו שעה אחת וכשישראל זוכין מאיר בהם כח האבות. ובגלות נסתר זה הכח בנפשות בני ישראל.

The shelaimus of Yisrael is that they should be drawn after the heart of the Avos as it is written in the future Hashem will return the heart of the Avos to their children and then will be the geulah. The Avos possessed only one heart to their Father in heaven and they never removed their love and cleavage from the creator even for a moment. When Yisrael merits, Hashem shines to them the strength of the Avos. In Galus this power of the Avos is concealed from them.
With this we can understand the opening passuk of the Parsha and the Rashi commentary. Rashi asks why is this parsha’s beginning closed when every other parsha is preceded by the space of nine letters before it. Chazal answer for at Yaakov’s death the hearts of Yisrael were closed and the tzaros to them commenced. Without the presence of Yaakov they forgot their connection with the Avos. Their failure to connect to them caused them to lose their true power of dibbur and ability to daven. That is why at the time of the geulah the Torah tells us that they finally we able to daven ואת צעקתם שמעת על ים סוף and Chazal comment תפסו אומנות אבותם they utilized the craft of the Avos. However, until then they were not connected to the Avos and they lost their ability to daven. That could be the reason why we take three steps back before we walk the three steps forwards before tefillah. What is the purpose of stepping backwards when we are landing up in the same place with which we started? The answer is to allude to the three Avos who founded the Shemoneh Esrai. That is why we mention the Avos at the beginning of the Shemoneh Esrai אלקינו ואלקי אבותינו אלקי אברהם יצחק ויעקב . It was they who fixed in the hearts of Klal Yisrael this power to stand before Hashem the King of Kings and daven. This is the meaning of the word daven. No it is not Yiddish, but rather an Aramic word דאבונהון which translates of the Fathers. If you pronounce that word fast enough then it sounds like davening just as we find in the words שלש סעודות which becomes shaleshudis, and יישר כחך  shekoach.

Rashi in Pesachim 5 writes that the letters of אך in the format of a certain gematria system equals letters of חץ. The relationship between the two is as follows. The word אך denotes minimizing and making smaller. According to above, theחץ  which represents tefillah and its success to go heavenwards and be accepted, depends upon one’s אך” degree”, how much one is nullified and negated to Hashem during tefillah. In tefillah we bow down four times to demonstrate our bittul and subjugation to Hashem. Part of this subjugation is to rid one’s heart from any other distraction and interest other than Hashem. In this manner his heart and the heart of the Avos connect with a devikus fueled by the Avos as if they too were davening with him.
This concept is included in the קשת  the bow which also alludes to bowing down. One must focus on his four bowings in tefillah to ensure that it is not stemming from habit and it is only mechanical. But rather, his heart must be also subjugated to Hashem at that time not just his knees and body. Only then he fuses his tefillah with that of the Avos, and as his bow is pulled back to his heart, his arrow has enough power to travel the distance all the way up to the Kisay Hakavod without any interference. The passuk says (Yeshaya 57,15) אשכן את דכא Hashem dwells by the low and downtrodden. This can be referring to one who attains this level of sincerity when bowing to Hashem. He has truly reached the level of bittul of אך through the ד, the four bowings during Shemoneh Esrai. He is a דכא which contains the letters of ד and אך. Hashem dwells with him because of his quality tefillah.

The word קשת is the acronym of קריאת שמע תפלה . The main part of Shmah is the first passuk of שמע ישראל which contains 25 letters with which we accept the yoke of Shamayim upon ourselves. The gematriah of דכא is also 25. So both Shemah and Tefillah are alluded to in the word קשת. This teaches us that only after accepting the yoke of Hashem are we prepared to daven the tefillah and connect to the Avos to be infused with their light and their hearts.