"Is Life Fully Human Wthout Christianity?"

So I posted this to Facebook:

h/t Father Robert Barron and the Catholicism Project.
 Read the Pope's Wednesday address here.

and immediately got this question from a friend:

Is life fully human without Christianity?

to which I responded:

Ah--thereby hangs a massive, massive theological discussion. Bleah--permit me a few really nuanced, seemingly non-answer answers.
--Christianity teaches that we are made in the image and likeness of God, which means we were created to be sons and daughters of God. This relationship extended beyond the simply legal and touches on the underlying nature of humanity. God intended us to be elevated by sanctifying grace to truly supernatural life--divinization by grace. He is God by nature, we are made to share in his divine nature by grace.

--We were created in communion with the created order and each other on a deep level, and in complete control of our intellect, our will, and our passions, all of which were rightly ordered and elevated by the sanctifying grace.

--We fell, and so the relationships were disrupted. The whole of Jewish and Christian history--salvation history--is the history of God's covenants which are ordered at healing the breach in the relationship between God and humanity. When humans cooperate with those divine efforts, we get saints and prophets. When we fail, we get calamitous consequences.

--All of God's grace, all access to the divine comes to us through Jesus Christ, which means all of God's grace passes into communion with the created order through the womb of Mary, which means through Israel, which means through the covenants with Israel and the new and everlasting covenant in Christ's blood.

--All salvation, redemption, and sanctification comes through Jesus Christ, both him personally and through his mystical body, which is the People of God, the Church, whose origins are in the Trinitarian communion of three persons in one nature. All grace, all access to God comes through Jesus Christ.

--Therefore, any grace or access to God which any human being anywhere in the world at any time experiences or receives comes to them through Jesus Christ.

--We are made according to a divine plan which requires humans in communion with God and living graced lives in order to be fully human, fully in the image and likeness of God.

--If you take seriously the claims of Christianity about the nature of our relationship to God, the created order, each other, and ourselves, then the answer to the question "Is life fully human without Christianity?" is no. This does not mean that non-Christians cannot live fully human lives, but rather that absent the covenants and the Church, then humans cannot return to the communion with God for which they were intended. They cannot access grace, since Christ and his Body the Church are the means through which all grace enters human history.

I'd be glad to elaborate on anything.

I thought the answer worth preserving.