Warning the friends about bad associations lurking among the members of one's own congregation! What a wonderful way to foster harmony and a feeling of Christian unity, to have each looking suspiciously askance at the person sitting next to him/her. Isn't the average JW paranoid enough, and now there's no respite for his vigilance so that he/she can't even let down his/her guard even within the sacred walls of the local Kingdumb Hall?
And if one is to limit friendships with the spiritually strong, who will help the weaker and less mature? And what if the spirutal giant you choose for your companion deems you too weak to be worthy of his/her friendship, what then?