In this case you should review your code a little. You should directly call the show method in your link and edit your controller to have it responding to JavaScript:
View code:
<%= link_to user.name, user_path(user), remote: true %>
Controller code:
def show
@user = User.find(params[:id])
respond_to do |format|
format.html
format.js
end
end
And create a new view called users/show.js.erb
$("#mydiv").html("<%= escape_javascript(render(:partial => '/users/user_show', :locals => {:user => @user})) %>");
This view is calling a partial view where you can render all your user data. This view is called users/_user_show.html.erb
<div class="myuser">
<%= user.name %>
</div>
Hope that helps