I recently read this book and took note of several passages that communicated (presumably without intention) with precision and profundity a template of God's love for us and ours in response to His.
"Love, genuine passionate love, was his for the first time. This he had never experienced at Judge Miller's down in the sun-kissed Santa Clara Valley. With the Judge's sons, hunting and tramping, it had been a working partnership; with the Judge's grandsons, a sort of pompous guardianship; and with the Judge himself, a stately and dignified friendship. But love that was feverish and burning, that was adoration, that was madness, it had taken John Thornton to arouse. This man had saved his life, which was something; but, further, he was the ideal master. Other men saw to the welfare of their dogs from a sense of duty and business expediency; he saw to the welfare of his as if they were his own children, because he could not help it."
We have experienced relationships that were purposeful, productive, protective, and pal-around (had to keep the "p" thing going, I apologize). We were created for relationship. But only one relationship provides that which our heart and soul find complete. It is in the passion of responding to God's amazing love that we find overflow of joy and dignity and charity and levity with regards to ourselves. Being joyfully indebted to one who has served you is one thing. To have this same One also be intent on further serving and loving you is another. We have experienced the generosity of time, energy, money, or service of another and felt indebted. How much more so when that same One does so without a implication of repayment and further continues to pursue and provide for you as though They are the one acting to repay you continually for something you cannot remember or imagine you are owed?
"Thornton alone held him. The rest of mankind was as nothing."
In a world where many may have influence for better or for worse, the reverance of one above all others ought to be reserved for God so much so that any and every other is regarded as nothing. Jesus commands a devotion so focused that all other commitments could be considered "hateful" in comparison to the love of Christ. This is not Christ asserting any should hate their mom, dad, son, or daughter; but rather asserting by hyperbole the degree to which your first priority in Him is above and beyond that of any and every other priority that would follow (even that secured as second priority).
"For Thornton, however, his love seemed to grow and grow. He, alone among men, could put a pack upon Buck's back in the summer traveling. Nothing was too great for Buck to do, when Thornton commanded."
Buck would do anything for Thornton. Nothing was too much to ask. If it was Thornton asking, the answer was always, "Yes." I hope my heart would be as this towards God and thank God that His Christ was so devoted to His Father as to secure my eternal hope by His perfect obedience and devotion to God on my behalf.
"He had caught the contagion of the excitement, and he felt that in some way he must do a great thing for John Thornton."
It is a natural response to endeavor to do a great thing for God in response to the greatest thing imaginable He already has done for us. It is a beautiful thing to observe in another when you know its sincerity is not seasoned with penance. There is a beauty in those, who have fully accepted and realized the love of God in Christ for them, working so hard to make the most of the evil days in order to make so much of Him in them.
There is a reason this book makes the top 100 for men HERE. It does document and capture the desire to lead and survive among a world of "kill or be killed" (or perhaps more literally dog-eat-dog *ba-dum-dum-chi*). It is a half-time speech to the men of the world to rise up and take something (which exists by nature an impulse easily prodded), but I found its most poignant power in the themes of love begetting love and selfless sacrifice begetting selfless sacrifice (which exists in Christ an impulse that cost Him everything to impute).