Apparently there is a saying that has to do with holding the tenor of one's way, meaning to keep up good work, stretched in discipline towards the desired end, not straying here and there. With the heart in the right place. I was looking at the Greek origins of this phrase (III), and concluded that perhaps we might loosely translate it as keeping to the straight and narrow.
So this virtue is associated with the voice, rather with stretching - of sinews, ropes, equipment, the voice, the mind. The voice is just one manifestation of this principle of tension and straining, though the association of an idea with its material or figurative component confuses many.
The truth is not always visible, but is always present. When it is silent and withdrawn like the bookish friend that is oneself, other people with other agendas may try to appropriate it. I once met a stringer posted overseas by a reputable international publication who said, "I don't know the first thing about this place." Myths are crafted, perhaps by the tone deaf.
Who are those people howling in packs, voices all clashing into one another, no clear stand, no clear figuratively material picture.
A friend related a story of how the other day, tired from all her clients' demands, she stretched out on one of the lawns that separates a main road from a walkway leading to a park. A woman approached her asking, aren't you scared of snakes? And then rattled off a strange sequence of events that she had knit together in her mind as 'proof' of how one ought to be afraid. My friend commented that so much attempts to tempt us away from peace of mind.
Indeed, it seems in hard times that we are set up against ever more material (not even abstract!) problems that force us to reveal our true colours. Hopefully the problems increase our resolve to do the right thing. When Aristotle wrote (3 - 6) of happiness, he explained that in our pursuit of it, we mustn't follow the example of tyrants, amusing themselves as they do, but pursue virtuous activities that relax us. Any slave can enjoy physical pleasure, he wrote, but no one would say that the slave is happy. To live the good life is to keep the good tone.