[quote="Norseman82, post:31, topic:180642"]
There is no separate vocation to "single life". According to the CCC, it is marriage or "virginity for the sake of the kingdom", which is further clarified as priestly ministry and consecrated life.
And according to the CCC, marriage is the vocation that is instilled in our nature.
Except for the obvious vocations to the ordained/religious life, what is this based upon?
You obviously haven't read on the single life in the Catechism. I'll post it here. All are called to a religious life, be it laity or consecrated religious. Man is a religious being. The single life is an acceptable vocation of the Church.
1618 Christ is the center of all Christian life. The bond with him takes precedence over all other bonds, familial or social.113 From the very beginning of the Church there have been men and women who have renounced the great good of marriage to follow the Lamb wherever he goes, to be intent on the things of the Lord, to seek to please him, and to go out to meet the Bridegroom who is coming.114 Christ himself has invited certain persons to follow him in this way of life, of which he remains the model:
"For there are eunuchs who have been so from birth, and there are eunuchs who have been made eunuchs by men, and there are eunuchs who have made themselves eunuchs for the sake of the kingdom of heaven. He who is able to receive this, let him receive it."115
1619 Virginity for the sake of the kingdom of heaven is an unfolding of baptismal grace, a powerful sign of the supremacy of the bond with Christ and of the ardent expectation of his return, a sign which also recalls that marriage is a reality of this present age which is passing away.116
1620 Both the sacrament of Matrimony and virginity for the Kingdom of God come from the Lord himself. It is he who gives them meaning and grants them the grace which is indispensable for living them out in conformity with his will.117 Esteem of virginity for the sake of the kingdom*118 *and the Christian understanding of marriage are inseparable, and they reinforce each other:
Whoever denigrates marriage also diminishes the glory of virginity. Whoever praises it makes virginity more admirable and resplendent. What appears good only in comparison with evil would not be truly good. The most excellent good is something even better than what is admitted to be good.119
1658 We must also remember the great number of single persons who, because of the particular circumstances in which they have to live - often not of their choosing - are especially close to Jesus' heart and therefore deserve the special affection and active solicitude of the Church, especially of pastors. Many remain without a human family often due to conditions of poverty. Some live their situation in the spirit of the Beatitudes, serving God and neighbor in exemplary fashion. The doors of homes, the "domestic churches," and of the great family which is the Church must be open to all of them. "No one is without a family in this world: the Church is a home and family for everyone, especially those who 'labor and are heavy laden.'"
2232 Family ties are important but not absolute. Just as the child grows to maturity and human and spiritual autonomy, so his unique vocation which comes from God asserts itself more clearly and forcefully. Parents should respect this call and encourage their children to follow it. They must be convinced that the first vocation of the Christian is to follow Jesus: "He who loves father or mother more than me is not worthy of me; and he who loves son or daughter more than me is not worthy of me."
2349 "People should cultivate [chastity] in the way that is suited to their state of life. Some profess virginity or consecrated celibacy which enables them to give themselves to God alone with an undivided heart in a remarkable manner. Others live in the way prescribed for all by the moral law, whether they are married or single." Married people are called to live conjugal chastity; others practice chastity in continence:
There are three forms of the virtue of chastity: the first is that of spouses, the second that of widows, and the third that of virgins. We do not praise any one of them to the exclusion of the others. . . . This is what makes for the richness of the discipline of the Church.