Question: Why was baptism by John so crucial for Jesus, but not for Jesus’ followers?
Answer: The baptism by John is the last in a number of rituals established by God as a part of the progressive preparation of the human race for the coming of the Messiah. The initial stage in this preparation was the formal establishment, on Mount Sinai, of the community of Israel, the holy people beloved by God, from whom the Messiah would come.
The community was established by the Old Law, and had as its primary commandment the worship of the one God, and so differed from paganism. The reason this was so is that it would be impossible for the Messiah to be the Son of God if there were many gods. Since the Law was calling the human race back from the materialism which resulted from the Original Sin, in addition to the prescriptions regarding monotheism, there were moral prescriptions by which the community was to demonstrate the kind of life to be lived toward one’s neighbor by someone who believed in one God. Thus, the Old Law had three kinds of precepts: moral, ceremonial, and juridical.
The moral precepts were identical with the Ten Commandments as a whole, and implemented the natural law concerning things like the necessity of worshipping the one God. They also expressed the attitude toward neighbors, in forbidding murder, adultery, theft, and the like. The ceremonial precepts regulated everything regarding the proper worship of the one God, reserved to the community of Israel, from the temple worship to circumcision. The juridical precepts regulated everything special to the Israelite community in practice towards one’s neighbor, like the law of first fruits.
Circumcision was included among the ceremonial precepts because it was the cultic means of initiation into the community of Israel. As such, it involved a direct testimony to the patrimony of Israel, including the fact that the Messiah and Redeemer would come from this community. Though as a “sacrament” of the Old Testament, it could not bring grace and justification in itself, as a testimony to faith in the Redeemer, it could cause grace from the disposition of the recipient (ex opere operantis). As Thomas Aquinas says: “Circumcision was protestation of faith; wherefore by circumcision, also men of old were aggregated to the body of the faithful.” (Summa Theologiae, III, 70, 1, ad corp.) It was thus a preparation for the sacrament of the New Law which is baptism.
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Question: What are the differences in mercy, compassion, and pity as Jesus demonstrated in the Gospels, and that we also read about in the Old Testament, particularly in the Psalms?
Answer: The Old Law and the New Law are not two specifically different kinds of law. They are both the one, divine, and revealed law of God. The difference has to do with a progressive revelation and preparation of a materialistic world in becoming more and more open to spiritual realities. They are thus related as imperfect and perfect. This difference is seen in many different ways.
First, the Old Law had many commandments because the people were like children without a developed interior life of virtue. The New Law has relatively few commandments because it is primarily the grace of the Holy Spirit dwelling in the heart of each Christian soul. Second, the Old Law taught what was right, but did not give a person the ability to follow it as it did not, in itself, communicate grace. Since the New Law is the grace of the Holy Spirit dwelling in the heart of the Christian, in itself, it demands love as the basis for whatever is done. The Old Law was ordered specifically to identify the need for repentance and grace by pointing out sin. The New Law cures the very sin which it points out. In other words, the difference between the Old Law and the New Law must be the spiritual maturity it induces in the soul, a spiritual maturity caused by both the presence of sanctifying grace, which is union with the Trinity, and conformity to Christ.
The merciful love spoken of in the Old Testament, and lauded in the Psalms, for example: “O give thanks to the Lord, for He is good, for His mercy endures forever” (Psalm 136[135]), is identical with the merciful love of Christ, Mercy is the result of sanctifying grace. In fact, every verse in this Psalm demonstrates that the merciful love of God is at the origin of each action on the part of God with the people of Israel. The Talmud calls this Psalm the “Great Hallel (thanksgiving, praise).” This mercy is, of course, begun in the love by which God brings creation into existence, but bears more clarity in creating man in God’s image, and then, finally, in inviting the human race to communion and blessedness.
The difference between the mercy of Christ, and the mercy spoken of in the Old Testament, is the difference between promise and final fulfillment. The divine love and mercy expresses the final transformation of the human race in the face of sin, the preparation for which is taught in the Old Testament. Of course, people in the Old Testament could be justified by grace in their faith in the future Messiah, but they could not be conformed to Christ since he had not yet come.
Christ demonstrates the deeper mercy to us by assuming flesh, dying on the Cross though innocent, and ultimately sending the Holy Spirit into the Church on Pentecost. By Baptism, we participate in His own Mercy, shown to us in His human heart burning with divine love, where we are not only elevated by grace, but also share completely in His own mission to bring mercy and grace to the world. The grace of the Hypostatic Union allows us to experience the full measure of divine love, as there cannot be a more complete experience of this than that the Word should take flesh to atone for our sins.
As a result, each of us who has experienced mercy is called upon to show a new personal depth of this love in our actions. After loving God, the giving of mercy is the most graphic expression of one who has been redeemed. “The sum total of the Christian religion is implemented principally in mercy; but the inward love of charity, whereby we are united to God, preponderates over both love and mercy to our neighbor.” (Thomas Aquinas, Summa Theologiae, II-II, 30, 4, ad 2) So the merciful love invoked in the Psalms is the same as the merciful love of Christ, but it has greater effect, and is demonstrated in the more obvious words and works of His Son. They both involve divine love, which is transforming. In the second case, the transformation includes the inspiration of the Holy Spirit, so unlike the Old Testament, the works by which this mercy is implemented are spontaneously known, and do not have to be prescribed. They should be obvious to someone who enjoys the presence of the Holy Spirit.
I was told that the purpose of the baptism of Jesus was to sanctify the water for us and I have seen references to this in the Church fathers.