For me, it seems as if people want government or other people to solve their problems. It's easier to complain about others than to take responsibility and power upon ourselves to solve problems. When things go bad, it seems like people criticize God, but when things are going well, it's because of something they themselves figured out and did. I also see the analogy of the arrow as being rephrased as "what goes around comes around." The longer we find fault in others only makes us blind to the problems within ourselves.
This quote is presented in another post in this forum. One of the replies there explains that William Temple was the Archbishop of Canterbury from 1942-1944. Speaking as a religious leader, my interpretation of his comments is that he was bemoaning the decline in peoples' ability to use faith as an explanation for things that cannot be explained otherwise. I think he was calling for people to stop complaining when things can't be rationally or scientifically proved and to return to a willingness to accept the unexplainable by exercising faith.
One way to look at this is to say that it is bemoaning a loss of religiosity in the England of Temple's day. England's society was starting to move towards its current lack of much in the way of religious belief. Temple can be interpreted to be saying that his time was one in which people were unwilling to have faith in anything and that this lack of faith was going to end up harming their society.