“And God created man to his own image: to the image of God he created him: male and female he created them” (Gen. 5:2). “A man shall leave his father and mother and cling to his wife, and they shall become one flesh” (Eph. 5:31). “Go forth and multiply, fill the earth and subdue it” (Gen. 1:28).
For millennia the Church has received these and all of the Scriptures together, under the infallible guidance of the Holy Spirit, to lead us “into all truth.” In doing so, as Mater and Magistra, Mother and Teacher, the Church unfailingly communicates the love and plan of our true Father in Heaven.
Thus the Church teaches that marriage is always and only between one man and one woman, whose role is primarily to procreate new life together with God out of the love and the home they make and share together according to His holy plan. That’s the easy part.
Church Tradition offers a solid and cohesive plan of life, now and eternally. How we live now determines how we will live after this very brief earthly sojourn, whether eternally blessed with God or condemned with the loveless and Godless to Hell forever.
Love is the hard part. Not God’s love, which so evidently comes to us through the truth, creation, and in so many other ways. Everything revealed about God is brought together above all in Jesus Christ, who is the “perfect Revelation of the Father.”
Love for human beings is ever a challenge because of our ever-present propensity for sin. The culture rejects the truth about our wounded nature. Having gotten that fundamental fact wrong, society and the so-called intelligentsia, and those who desire to be widely accepted as such, are simply “the blind leading the blind,” and as a result many are falling into the predictable “pit” about which our Lord lovingly warned us (Matt. 15:14).