O Lord, All-Knowing and Unknowable God, whose Son hath warned that he shall return like a thief in the night, and that no man on earth, nor any angel in heaven, knoweth the time of his coming, but only thee: Save us from arrogancy and pride, and from vain presumption; for not every man that crieth, “Lord, Lord”, shall enter into the kingdom of heaven. Grant us to accept the choice which thou hast foreordained for us, that they who lead the way may walk in humility, and a full understanding of their unworthiness; and that they who follow may persevere in faith, and in the knowledge of thy mercy and loving–kindness. For though one in the field shall be taken, and the other left, yet are both sinners, and precious in the sight of the Lord. And this we beg in the name of Jesus Christ, thy Son our Lord. Amen.
This prayer was first used at Evensong for the Sunday after the Ascension, 2011. It is available, along with a Collect for Aid against All Gullibility, in a PDF file (also linked from the Library page).