Ecclesiastes 4:9-12

Two are better than one because they have a more satisfying return for their labor; for if either of them falls, the one will lift up his companion. But woe to him who is alone when he falls and does not have another to lift him up. Again, if two lie down together, then they keep warm; but how can one be warm alone? And though one can overpower him who is alone, two can resist him. A cord of three strands is not quickly broken.