I've posted a piece about the migration from youth to adulthood with my take on it intermixed.

"When we reach the end of our teens our bold young faith that thinks nothing worthy can be hard if only met with good resolve, ends up dashing the familiar joy with new longings and repentances."

I begin to reminisce about days when I saw life and all I thought it had to offer and I was so sure I was well equipped to handle all that would come my way. So eager to jump into the fray. With youth comes the boundless optimism as well as energy, “fired at first sight with what the muse imparts, in fearless youth we tempt the heights of arts.” I think much of my life has been spent in intoxicated thinking that I had some wisdom or understanding of life, only to find I have been drinking shallow. So naively confident that I could see the heights, and the depths of life, taking life on the surface, thinking I saw all there was. “Short views we take, nor see the lengths behind”.
As life unfolds her endless mysteries it so humbles the soul, the infinite climb to reach just the base.

"Amid the fiercer struggle that sets in, the great thing needed is strength of Moral Denial, the courage to say No to all questionable people and unquestionable fiends."

When we get out on our own, and face life with its full force, we are so deluged with new and lesser moralities, it would take a saint not to compromise our childhood values. Freedom always brings its excesses; and where we once saw few R rated movies, now the parental restraint is gone and our weakened conscience allows for concession and with new friends, freedoms and control we are faced with fiendish sights and sounds, our youthful beliefs are challenged and some are held to but others bow to the blush of peers. All of this repels us and entices us at the same time, we find our youthful mind was no match for adult debate and our individual convictions give way to the prevailing wind and tide.  

"Meanwhile, the very faculties of thought are changing too. The appetite for facts is passing into an eagerness for truth, full also of deep anxieties."

I think this thought is very insightful, as a child most of our world of education is about facts, not theory or philosophy; and as we enter the world we are faced, if not accosted by, a thousand searches for truth we had never even considered much less held too. Most of our adversaries are hardly scholars or even second rate philosophers, but merely echoes of fragmented truth that have never been tested or tried. Those that you trusted for truth who have the benefit of a half century of seeking, and have seen, "Many a gaudy bubble that has not risen, but rather glitter, and burst; and conversely, many a modest good take secret root and grow." are quickly abandoned and dismissed. But we are humans, and we are drawn to the novel, the unconventional and the nonconformist's view has a strange appeal. 

"Sometimes this noble passion degenerately tends to disagreeable dogmatism, from the mind's having lost its childish source of trust, and not having gained the manly , and for awhile holding the faith neither in meek dependence on authority, nor in genial repose on the universal Reason and Conscience, but by the little personal tenure of private argument."

 I like the phrase, "Little personal tenure of private argument." This is the arena where most of our curious and novel debates take place, private discussions where new thoughts are hotly debated and everything is thought to be, because of our inexperience, new and enlightened; but as Solomon said thousands of years ago, "There is nothing new under the sun."  

 "And sometimes, it is productive of dark agonies of doubt and loneliness, drearier than death; leaving the soul exposed upon the field of conflict, without a God to strive for, or a weapon for the fight."

In this last thought I fear he doesn't go far enough, because he begins with, "And sometimes," and I suppose it is true, sometimes a new thought gives wind to our wings and we take flight, but with time our wings of wax melt with testing. Now this process may be repeated over and over again by some. One novelty of thought pursued after another, but with some, the callings of their childhood faith shines bright enough and they return home, not to a childhood faith once more, but to a more strenuous faith, a fuller understanding of simple truths that protect and lift the heart to heights that no cunningly devised fable or scientific rhetoric can approach, because this life is one of the heart, the spirit: and that alone comes from the shadow of His wings, the solid rock of His truths, and the security of Christ's love. And abiding in His love arms us with all the weapons we need for life and love.