SOOOO many wonderful choices! I'll limit myself.
A man gives of himself fully in charity and love.
- All of the Song of Solomon
Put me as a seal upon thy heart, as a seal upon thy arm, for love is strong as death, jealousy as hard as [Sheol], the lamps thereof are fire and flames. Many waters cannot quench charity, neither can the floods drown it: if a man should give all the substance of his house for love, he shall despise it as nothing. Song of Solomon 8:6-7
All of 1 Corinthians
Be on the alert, stand firm in the faith, act like men, be strong. Let all that you do be done in (charity) love. 1 Cor 16:13-14
Ephesians 5:25-32
Husbands, love your wives, as Christ also loved the church, and delivered himself up for it:
That he might sanctify it, cleansing it by the laver of water in the word of life:
That he might present it to himself a glorious church, not having spot or wrinkle, or any; such thing; but that it should be holy, and without blemish.
So also ought men to love their wives as their own bodies. He that loveth his wife, loveth himself.
For no man ever hated his own flesh; but nourisheth and cherisheth it, as also Christ doth the church:
Because we are members of his body, of his flesh, and of his bones.
For this cause shall a man leave his father and mother, and shall cleave to his wife, and they shall be two in one flesh.
This is a great sacrament; but I speak in Christ and in the church.
All of Theology of the Body
...that is, the capacity of expressing love, that love in which the person becomes a gift and—by means of this gift—fulfills the meaning of his being and existence. Let us recall here the text of the last Council which declared that man is the only creature in the visible world that God willed "for its own sake." It then added that man "can fully discover his true self only in a sincere giving of himself" -The Man-Person Becomes a Gift in the Freedom of Love
And my very favorite summation of what it means to be a man:
If
If you can keep your head when all about you
Are losing theirs and blaming it on you;
If you can trust yourself when all men doubt you,
But make allowance for their doubting too;
If you can wait and not be tired by waiting,
Or, being lied about, don't deal in lies,
Or, being hated, don't give way to hating,
And yet don't look too good, nor talk too wise;
If you can dream - and not make dreams your master;
If you can think - and not make thoughts your aim;
If you can meet with triumph and disaster
And treat those two imposters just the same;
If you can bear to hear the truth you've spoken
Twisted by knaves to make a trap for fools,
Or watch the things you gave your life to broken,
And stoop and build 'em up with wornout tools;
If you can make one heap of all your winnings
And risk it on one turn of pitch-and-toss,
And lose, and start again at your beginnings
And never breath a word about your loss;
If you can force your heart and nerve and sinew
To serve your turn long after they are gone,
And so hold on when there is nothing in you
Except the Will which says to them: "Hold on";
If you can talk with crowds and keep your virtue,
Or walk with kings - nor lose the common touch;
If neither foes nor loving friends can hurt you;
If all men count with you, but none too much;
If you can fill the unforgiving minute
With sixty seconds' worth of distance run -
Yours is the Earth and everything that's in it,
And - which is more - you'll be a Man my son!
-Rudyard Kipling