This is not an exhaustive definition of Masculinity, there is much more to masculinity, but there is not less. And make no mistake it is possible for a man embody many traits that socially are associated with masculinity (i.e. hunting, fishing, fighting, sportsmanship, be an outdoorsman) while at the same time remain "immature" with regards to true and biblical manhood. If there does not exist this "sense of responsibility" to lead, provide, and protect, his masculinity is at best incomplete and may even be distorted...
The word sense here is most appropriate because it does not merit the necessity of a woman or the interaction with women for a man to develop or to have maturity with regards to his masculinity. For example if he is single in the mission field working with indigenous groups, he is at combat, in a monestary, imprisoned, these circumstances do little to negate ones maturity. Neither does this sense need to be actualized in order to meet the criterion for mature masculinty. The man can remain single and celibate and still have a mature sense of responsiblilty that permeates and influences the way he interacts with women, talks to women, relates to pornography or sexually illicit material found in cultural media of all kinds, and even the way he interacts with the marriages of men around him. It also does not mean that he in all situations is enabled to fulfill this burning desire within him. For example a man who has contracted a life crippling disease that leaves him bed ridden and unable to provide for and protect his wife is still capable of recognizing and sensing this desire to provide for and protect for his wife and children even if the wife has now assumed the responsibility as breadwinner.
The term "benevolent" is meant to express the manner of this responsibility and indicate how it is to be served to the women around him. Men are meant to lead biblically as Christ demonstrated becoming the servant in all relationships around them, not lording their leadership in a self-aggrandizing or dictatorial way. But rather they are to fully relay the expression of the golden rule with regards to their female relationships. (Matt 6)
It is a "responsibility", it is a God-given trust for the good of all his creation, it is a duty, one for which men will give an account. Clearly illustrated in Genesis 3:9 when God says first to Adam "where are you?" even may have sinned before Adam but he was the first called to give an account. This does not belittle the responsibility of women, it simply signifies mans unique responsibility.
To "lead" this is perhaps the most often misunderstood trait of masculinity. The term "lead" is somewhat nebulous pending the context in which it is used. Biblical and masculine leadership expresses itself not in the demand to be served but in the strength and conviction to serve and sacrifice for the good of those he is leading and in this case specifically for the good of woman. It imitates and embodies the model laid out by the teachings of Jesus and his moving sacrifice on the cross for his bride. It does this by serving and leading in ways that attempt to draw out the strengths of those on whom their leadership falls. Simply put a good leader does not aim to demonstrate his superiority over others but rather to bring out all of the strengths that will move them in their desired direction. The man must do this not by assuming and enforcing his leadership but advocating for it.
To "provide" is not to belittle or inhibit a woman's role in maintaining support for the family or for society but that his benevolent and loving desire to provide practically unfolds in that when their is no bread on the table it is the man who should feel a responsibility to get it there. This does not mean that the women can't help. This is clearly seen from Gen. 3 when the man receives his curse to work the land.
To "protect", at the core of mature manhood is the desire to protect. The mature masculinty produces a desire to suffer for the safety of other, to step forth into harms way in hopes of protecting his wife, family, loved ones, life, or truth. Few would contend that this is without virtue, just as few would lable it the women's job to play this role of protection in the place of her husband or for his protection. Such an opinion would be a distorted and perverted one that across cultures does not seem to align.
All of these actions and virtues lie deeply rooted in a regenerated heart that has been transformed, it is only through this that man is able to truly love like Christ loved the Church. But manhood has little to do with being married, just as it has little to do with much of what society would deem "manly". It is mans God-given responsibility to lead, provide for, and protect the women no matter the nature of their relationship. The clearest example of mature masculine leadership took place on the cross, and we as men are now charged to glorify God by behaving, leading, protecting, and providing for those around them, especially the women in their lives.