Genesis 41:1
וְהִנֵה עמֵֹד עַל־הַיְאַֽרֹ
and behold, he was standing by the Nile
The preposition עַל has the connotation of nearness, proximity. There is another meaning, however. עמֵֹד עַל is a biblical idiom, as in: וְהִנֵה ה’ֹ נִצָב עָלָיו – And behold, the Lord was standing over him (Gen 28:13), that is, paying special attention to him (Rashi). The word עַל describes a relationship. Jacob dreamt of God’s concern for him.
The Nile is not merely a river. The economy of Egypt in antiquity depended on the Nile, as it does today. The Torah speaks of how this unique geographical feature was responsible for either abundance or famine. For the land where you go to possess, it is not as the land of Egypt … where you sowed your seed and watered it with your foot as a garden of herbs (Deut 11:10). Local rain did not play a role in the agricultural economy. Life instead depended upon the Nile. Rashi says, No other river is called “the River” except the Nile, because the whole country consists of artificially constructed canals and the Nile flows into them and fills them with water since rain does not fall regularly in Egypt as in other lands. The river became the very symbol of Egyptian civilization. Pharaoh thus saw himself עמֵֹד עַל־הַיְאַֽרֹ, concerned with the destiny of Egypt as a land and as a people.
When Pharaoh’s sages attempted to make sense of his dreams, he summarily rejected their interpretations: וְאֵין־פוֹתֵר אוֹתָם לְפַרְעַֽהֹ. (v. 8) According to Rashi: There were those who interpreted them, but not for Pharaoh. Their voices did not enter his ears and he found no relief in their interpretations; they were saying, “You will beget seven daughters, [and] you will bury [these] seven daughters.” When Pharaoh saw himself עמֵֹד עַל־הַיְאַֽרֹ , on the river that was the cornerstone of the Egyptian economy, he knew that his dreams were connected to his nation’s very destiny. He therefore rejected any interpretation that limited the scope of these dreams to his personal life.
In his later description of his dream to Joseph, Pharaoh used the term עמֵֹד עַל־שְפַת הַיְאַֽרֹ : Pharaoh was standing on the bank of the Nile (v. 17). Unlike the earlier phrase here עמֵֹד עַל־הַיְאַֽרֹ , the phrase עַל־שְפַת הַיְאַֽרֹ has no connotation other than the physical description of the scene in his dream. Joseph’s interpretation, however, fully accounted for Pharaoh’s understanding of the dream’s broad implications (Vision and Leadership, p. 23).