Ave crux spes unica

Ave crux, spes unica is a Latin pious expression or motto meaning "Hail to the Cross, our only hope." The expression has a long history in Catholic piety and is a motto occasionally used by bishops and Catholic institutions. It is the motto of the Congregation of Holy Cross, Edith Stein, and of Daniel Cardinal DiNardo, Cardinal Archbishop of Galveston-Houston.

It may be found inscribed on the back of the Processional Crucifix in the Church of SS. Peter and Paul, in the village of Yattendon, Berkshsire, England. The inscription forms the shape of a cross with OCRVXAVE downward and SPESVNICA forming the cross piece. The two share the "V" in the middle.

"Spes Unica" is also the inscription under the Cross at the summit of the facade of the Basilica of St. Paul Outside the Walls, one of Rome's four major basilicas.

The American novelist, Edith Wharton, chose this inscription for her gravestone at Versailles.

The origins are thought to be a stanza of an ancient Roman hymn to the True Cross of Christ, dating back to the sixth century, Vexilla Regis Prodeunt (or just Vexilla Regis). The ninth stanza is as follows:

O Crux ave, spes unica,
hoc Passionis tempore!
piis adauge gratiam,
reisque dele crimina.

which roughly translates:

O hail the cross our only hope
in this passiontide
grant increase of grace to believers
and remove the sins of the guilty.

As a stand-alone motto the expression can appear as Ave Crux Spes Unica or as in the original hymn, O Crux ave, spes unica, meaning essentially the same.

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