There is no person in life past or present, save Jesus, who is beyond some critique. We often understand this intellectually, but practically it often comes out that this or that person we view as completely beyond any critique.
It is easy for us to glorify people as beyond critique. It is our nature to wish to have people to look to past or present who cannot err. It makes things simple.
The reality is that all people are fallen and have issues. If someone has a critique of a figure we respect it does not make the person our enemy. The person's critique may be completely off base but it does not make the thinking of the person unworthy of listing to necessarily.
You see too often we judge a person's thought so quickly. Oh they like reading Karl Barth and I don't like Barth therefore they aren't worth talking to. Or they are fond of reading Vanhoozer and I like Vanhoozer therefore they are worth talking to.
It is subtle and rarely so blatant but often we judge a thinker by who they like before we hear what they have to say. It is not that who a person likes to read had no influence on who the person is, but rather we may find many people who enjoy reading similar figures as ourselves who have nothing of value to say and many people who enjoy reading people we are skeptical of who have much of value to say.
You see who a person likes to read or finds interesting to read is of little importance compared to what a person thinks and does. We often judge people for the most odd reasons. Of course we are fallen but the more we accept that we do make odd decisions and have done so the less prone we become to make odd decisions in the future.
We often need to wait and see. We often judge too early in a conversation if a person's thought will or will not be good and thus we often err in our judgement.