Our Gemara on Amud Aleph references the idea that all land is linked, allowing the act of acquisition of one property to affect the acquisition of another, unlike chattel (movable objects). Sefer Daf al Daf quotes Rabbi Akiva Eiger (Shu”t 4:11) who asks a question based on this teaching. The verse in Bereishis (28:13) tells us that Hashem promises Yaakov that the land he was sleeping on would one day become his possession:

הָאָ֗רֶץ אֲשֶׁ֤ר אַתָּה֙ שֹׁכֵ֣ב עָלֶ֔יהָ לְךָ֥ אֶתְּנֶ֖נָּה וּלְזַרְעֶֽךָ

"The land upon which you are lying, I will give to you and to your descendants."

The Gemara (Chulin 91b) states:

בראשית כח, יג) הארץ אשר אתה שוכב עליה וגו' מאי רבותיה אמר רבי יצחק מלמד שקפלה הקב"ה לכל ארץ ישראל והניחה תחת יעקב אבינו שתהא נוחה ליכבש לבניו

The Gemara explains another verse from Jacob’s dream: "And behold, the Lord stood over him and said: I am the Lord, the God of Abraham your father and the God of Isaac. The land upon which you lie, to you will I give it, and to your seed" (Genesis 28:13). The Gemara asks: What is the greatness of this promise, i.e., why is it expressed in this way despite the fact that in a literal sense Jacob was lying on a very small amount of land? Rabbi Yitzḥak says: This teaches that the Holy One, Blessed be He, folded up the entirety of Eretz Yisrael and placed it under Jacob, our patriarch, so that it would be easy for his children to conquer.

Rabbi Akiva Eiger asks, why was it necessary to fold all the land under Yaakov? Based on our gemara in Bava Kama, he could have acquired all the land, just the same, by resting on one part? He answers that while this might be true, it would not satisfy the statement in the verse, “land upon which you are lying,” which implies he was laying on ALL the land that he was to acquire.

Rabbi Akiva Eiger addressed the 'what' but not the 'why.' Why did Hashem need to have Yaakov rest underneath all of the Land of Israel? Mizrachi (Bereishis 28:13) explains that there is a difference between potential and actual. By actually laying on the entire land, this brought the blessing from potential to actual, making it far easier for Yaakov’s descendants to conquer the Land of Israel.

What does Mizrachi mean? I believe he is speaking of the idea that though Hashem may give a blessing and that thing will eventually come true, it does not mean it will be easy. We believe Moshiach will come one day soon, but has it, and will it, come easy? We believe that one’s shidduch (Sotah 2a) and parnassah (Beitzah 16a, Kiddushin 82a) come from God, but does that mean it will come easily? We must recognize that many of God’s blessings, even if promised, come in their own time and way, sometimes quickly and sometimes more slowly, sometimes we have to work hard for them, and other times, with little effort.