From the traditional prayers of exorcism and blessing of salt:
Exorcism of Salt (necessary for Exorcism of Water)
P: O salt, creature of God, I exorcise you by the living (+) God, by the true (+) God, by the holy (+) God, by the God who ordered you
to be poured into the water by Elisha the prophet, so that its life-giving powers might be restored. [2 Kgs 2:20-21] I exorcise you so that you may become a means of salvation for believers, that you may bring health of soul and body to all who make use of you, and that you may put to flight and drive away from the places where you are sprinkled; every apparition, villainy, turn of devilish deceit, and every unclean spirit; adjured by him who will come to judge the living and the dead and the world by fire.
R: Amen.
P: Let us pray. Almighty and everlasting God, we humbly implore you, in your immeasurable kindness and love, to bless (+) this salt which you created and gave to the use of mankind, so that it may become
a source of health for the minds and bodies of all who make use of it.
May it rid whatever it touches or sprinkles of all uncleanness, and protect it from every assault of evil spirits. Through Christ our Lord.
R: Amen.
From a commentary on the Roman Ritual, on Baptism:
Salt is a condiment meant to
flavor foods and also
preserve them. Among some peoples it is given to a newly arrived guest in sign of hospitality and friendship. Among the Hebrews it was eaten to symbolize the binding nature of a compact. Christ told the Apostles: “You are the salt of the earth” (Mt 5.13). As salt acts on food to preserve it and keep it from spoiling, Christ’s followers are
to influence the world for good and to preserve from corruption the truths He taught them. In the rite of baptism salt is especially
a symbol of wisdom–that the subject be given a relish for heavenly doctrine; and a symbol of
a blessed immortality–that he be preserved from final corruption. In the ancient rite the first stage, enrolling of catechumens, terminated with the giving of blessed salt.
Salt was also placed in the mouths of those being baptized:
The priest puts a pinch of the blessed salt in the mouth of the child (to each one), saying as he does so:
N., take this salt in
sign of wisdom. May it be for you likewise a token that foreshadows everlasting life.
…
God of our fathers, God, source of all truth, we humbly ask you to be well disposed to your servant, N.
After this first taste of salt, let his hunger for heavenly nourishment not be prolonged but soon be satisfied. For then he will always pay homage to your holy name with fervor, joy, and trust. In your tender care, O Lord, lead him to the bath of water where one is born over again, so that taken into the family of your faithful he can finally attain the everlasting reward which you have promised; through Christ our Lord.
The Catechism of the Council of Trent teaches:
To the exorcism are added other ceremonies, each of which, being mystical, has its own clear signification. When, for instance, salt is put into the mouth of the person to be baptised, this evidently means that,
by the doctrines of faith and by the gift of grace, he shall be
delivered from the corruption of sin, shall experience a
relish for good works, and shall be delighted with the
food of divine wisdom.
More on salt
here.
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