Humanist vs. God

The Chovos Halivavos (gate of Love of Hashem chapter 4) says that Avrohom was tested in his love of Hashem three ways, bichal levavcha, nafshecha u'miodecha.  He was tested 1) monetarily in regard to if he would take money from the Sedomite king, 2) bodily, if he would do bris milah, 3) life, if he would sacrifice Yitzchak.  It sounds from the Chovos Halivavos that the test of Avrohom was would he fulfill the word of Hashem begrudgingly or would he do it with heslavus, feeling and wholeheartedly.  A similar idea is expressed in the Igros Kodesh section of the Tanya, Letter 21.  He asks what was the greatness of the akedah, many people have given up their life for Hashem's sake? He explains that the test was to see if Avrohom was willing to do the akedah with zrizus.

The midrash says that as Avrohom was preparing to slaughter his son his heart was happy to fulfill the word of Hashem but tears were streaming down from his eyes.  The midrash derives this from the fact that through the story of akedah it says Yitzchak, however when it comes to tying up Yitzchak on the alter it says Yitzchak bino, to indicate that Avrohom had feelings that Yitzchak was his son and cried.  It seems that through the whole journey to the place of the akedah Avrohom didn't view Yitzchak as his son, he viewed him as a korban, as a cheftzah shel mitzvah and therefore, was able to fulfill the commandment of Hashem with great simcha.  But in the final moment, when it came time to actually slaughter his son, the emotional wellsprings of fatherly love opened up within him.   

Rav Yitzchak Eizek Sher (see Chachmas Hamitzfon) is bothered why did Avrohom cry, didn't he know that Hashem's commandment is for the best?  He explains that part of the commandment was to feel bincha, yechidcha, asher ahavta, he had to feel love for Yitzchok and still be willing to slaughter him.  Therefore, Avrohom couldn't suppress the feelings of love for his son for part and parcel of the commandment was to feel the emotions of fatherly love, but yet overcome it to fulfill the desire of Hashem.

I am not convinced about the whole question of Rav Yitzchak Eizek Sher.  I think that itself is the point of the midrash, true there is a commandment from Hashem and Avrohom was wholeheartedly willing to fulfill it but that doesn't uproot the natural love a father has for his son.  Was Avrohom supposed to have no feelings as he was sacrificing his own son?  Are we expected to be men of steel and have no feelings at all?  Or, one has feelings, but they must bow to the will of God?  Rav Sher seems to be assuming if one gets a commandment of Hashem then one's feelings must go along.  I'm not so convinced.