If it chanced that after the fatigues of along journey he had to lodge with secular persons, he would first quench his thirst at some handy spring, fearing to draw attention to any excess in drinking from his intense thirst, due to his wearisome traveling on foot. This he was always most careful to avoid, not only in drinking, but in everything else besides.
I know what you're thinking. You're thinking that if this fellow weren't the canonized founder of my Order, I'd be knocking him as a hypocrite, or at least as no respecter of truth.
Or you may be thinking this is mighty rich, considering how he got his start as a preacher: his bishop, Diego de Acebes, recognized that making headway in preaching against the Albigensian heresy required travel on foot and begging, to match the austerity of the heresiarchs.
But St. Dominic seems to have had a very clear understanding both of the strength of the Truth and the fragility of man. The Order he founded manifests that trust in the power of Truth -- in fact, of faith in He Who is Truth -- to save those who encounter Him.
At the same time, though, St. Dominic was aware of how easily men invent excuses to avoid seeing the truth, and of the consequent necessity for preachers to provide no opportunity for excuses to develop. Anything that might distract a person's attention from the Gospel, even something as natural as a very thirsty traveler, was to be avoided if at all possible.
What serves the preaching mission? What interferes with it? Answer these questions, and you understand St. Dominic and his spiritual children. Live the answers, and you are his spiritual child.