“We will go along the king’s highway, we will not turn aside to the right hand nor to the left” – Numbers 20:17, JPS 1917 Tanach
The Children of Israel were ready to enter the Land. This was the generation after those who had believed the ill-report of the Spies. Yet, the shortest route into Eretz Canaan would pass through the territory of Edom. The Edomites were the descendants of Esau. Moshe appealed to the king of Edom, reminding him of the oppression of the Children of Israel, when enslaved in Egypt. Perhaps, he would have a moderate amount of compassion towards his brothers.
Moshe explained, that the Children of Israel would pass through Edom, travelling upon the king’s highway, neither deviating to the left nor to the right, as if to say, that the people would not enter the fields, nor the vineyards, and would pay for any consumption of water. (Incidentally, this is an excellent standard, for the lifetime journey of keeping to the straight and narrow). However, the king of Edom’s response was harsh; he refused passage through his kingdom. He backed up his refusal, saying that if they tried to pass, he would go against them with the sword. (His refusal represents the many obstacles in the way, on the derech towards Malchus Elokim).
The Sages emphasize that this is the way of Esau, based upon the blessing that his father, Isaac had given to him, “By your sword shall you live” (Genesis 27:40). On the contrary, Isaac, who was blind, said, “the voice is the voice of Jacob,” when his son, Jacob came to him for a blessing. The Sages infer that these words connote the value of prayer in regard to Jacob (Bereishis Rabbah 65:20). For, the sword of Esau is contrasted against the prayers of Jacob. Prayer is highly regarded as an effective means of seeking assistance from th L-RD. The sincere prayers of Israel will evoke a response from G-d (Rashi).