And it can be explained that the essence of friendship is loyalty and trust between the two parties, as the verse says (Deuteronomy 33:12): "Of Benjamin he said, 'The beloved of the Lord shall dwell in safety by him.'" This is based on what is said in the Gemara (Sotah 37a): "The tribe of Benjamin jumped and descended into the sea first, as it is stated (Psalms 68:28): 'There is Benjamin, the youngest, ruling them,' do not read 'ruling' but 'descended into the sea'." This means that friendship is a bond that includes trust and stability to the point of self-sacrifice, and it is a sign of the highest spiritual connection. Likewise, we find in David's eulogy for Jonathan that he emphasizes this point: "I am distressed for you, my brother Jonathan; you have been very pleasant to me; your love to me was wonderful, surpassing the love of women" (2 Samuel 1:26). Even though it is stated in the Gemara (Moed Katan 26a): "Saul – this is the prince, Jonathan – this is the head of the court," which means that Jonathan was a great leader of the generation, still David eulogized him primarily for the greatness of the friendship that was between them. As the Malbim explains there, their love was an inherent, wonderful love, far superior to utilitarian or pleasurable love. And one who has tasted the flavor of friendship with another person can from there attain the level of friendship towards the Holy One, Blessed be He (HaKadosh Baruch Hu).

And this is hinted at in the language of the Mishnah (Pirkei Avot 1:6), "Acquire for yourself a friend," referring to this level of love that one must literally acquire with money and the like, as it is a high spiritual acquisition because it includes loyalty and stability. Therefore, the sages called someone who is trustworthy regarding tithes a 'friend' (Tosefta Demai 6:10, and elsewhere).