Pour on Us the Spirit of Your Love

O Lord,
in your mercy pour on us
the Spirit of your love,
that those you have fed
with one heavenly bread
may be united in heart and faith;
through your Son, Jesus Christ our Lord,
who lives and reigns with you and the Holy Spirit,
one God, now and forever.
Amen.

Source: Leonine Sacramentary, possibly fifth century. Translated for A Collection of Prayers.

As a block paragraph:

O Lord, in your mercy pour on us the Spirit of your love, that those you have fed with one heavenly bread may be united in heart and faith; through your Son, Jesus Christ our Lord, who lives and reigns with you and the Holy Spirit, one God, now and forever.

Original in Latin:

Spiritum nobis, Domine tuae caritatis infunde, ut, quos uno caelesti pane satiasti, una facias pietate concordes. Per Dominum nostrum Iesum Christum Filium tuum, qui tecum vivit et regnat in unitate eiusdem Spiritus Sancti Deus per omnia saecula saeculorum. Amen.

See also: http://www.preces-latinae.org/thesaurus/Euch/SacrumConv.html