Throughout history Jews have been moser nefesh including sacrificing their children. Why is Avraham Avinu praised so greatly? Was the עקידה a greater test then many of the things that happened in the holocaust? The same question can be asked about Yosef. He is highly praised for withstanding temptation with Potiphar's wife. Again, is this really so great? Don't people withstand these temptations daily?
The answer is based on what R' Chaim Volozhin writes in Ruach Chaim (his commentary to Pirkei Avos). He explains that Avraham Avinu's nisayon was truly much greater then ours. He was the first one to overcome this nisayon and brought this power down from heaven and passed it along to his descendents. The Avos when they passed a nisayon were able to implant that strength into our spiritual DNA, so that we now already have that strength (the Ramban makes a similar point when he says maaseh avos siman l'banim). In other words, Jews have the strength to be moser nefesh only because Avraham Avinu was moser nefesh and brought this strength down to earth and passed it down to his descendents. In fact, it turns out that for us the nisayon is not nearly as great as Avraham's nisayon was because Avraham Avinu and Yosef paved the way. As Newton stated If I have seen further, it is by standing on the shoulders of giants. If we can overcome nisyonos it is because we are pygmies standing on the shoulders of the giants, the Avos.