Thomas Aquinas

“ Hence it was more beneficial that the Divine mysteries should be revealed to uncultured people under a veil of figures, that thus they might know them at least implicitly by using those figures to the honor of God. ”

“ A wise lawgiver should suffer lesser transgressions, that the greater may be avoided. And therefore, in order to avoid the sin of idolatry, and the pride which would arise in the hearts of the Jews, were they to fulfil all the precepts of the Law, the fact that they would in consequence find many occasions of disobedience did not prevent God from giving them many ceremonial precepts.
Reply to Objection 3: The Old Law lessened bodily worship in many ways. Thus it forbade sacrifices to be offered in every place and by any person. ”

“ But in the New Law the sacrifice is the Sacrament of the Altar. Therefore in the Old Law there should be no distinction between "sacrifices" and "sacraments."
Objection 3: Further, a "sacred thing" is something dedicated to God: in which sense the tabernacle and its vessels were said to be consecrated. But all the ceremonial precepts were ordained to the worship of God, as stated above (A [1] ) . Therefore all ceremonies were sacred things. Therefore "sacred things" should not be taken as a part of the ceremonies.
Objection 4: Further, "observances" are so called from having to be observed. ”

“ But when that which conduces to an end is weak and imperfect, it needs to be multiplied: thus many remedies are given to a sick man, when one is not enough to heal him. Now the ceremonies of the Old Law were weak and imperfect, both for representing the mystery of Christ, on account of its surpassing excellence ”

“ Now interior worship consists in the soul being united to God by the intellect and affections. Wherefore according to the various ways in which the intellect and affections of the man who worships God are rightly united to God, his external actions are applied in various ways to the Divine worship.
For in the state of future bliss, the human intellect will gaze on the Divine Truth in Itself. Wherefore the external worship will not consist in anything figurative, but solely in the praise of God, proceeding from the inward knowledge and affection, according to Is. ”

“ When that which conduces to an end is sufficient to conduce thereto, then one such thing suffices for one end: thus one remedy, if it be efficacious, suffices sometimes to restore men to health, and then the remedy needs not to be repeated. ”