Just adding back the parts your leaving out that disagree with your post here (the full posts being in
post # 449 and
post # 450...
Catechism of the Catholic Church
Catechism of the Catholic Church - The third commandment
SUNDAY - FULFILLMENT OF THE SABBATH
2175
SUNDAY IS EXPRESSLY DISTINGUISHED FROM THE SABBATH WHICH IT FOLLOWS CHRONOLOGICALLY EVERY WEEK; FOR CHRISTIANS ITS CEREMONIAL OBSERVANCE REPLACES THAT OF THE SABBATH. In Christ's Passover, Sunday fulfills the spiritual truth of the Jewish sabbath and announces man's eternal rest in God. For worship under the Law prepared for the mystery of Christ, and what was done there prefigured some aspects of Christ:107
Those who lived according to the old order of things have come to a new hope,
NO LONGER KEEPING THE SABBATH, BUT THE LORD'S DAY, in which our life is blessed by him and by his death.108
2176
THE CELEBRATION OF SUNDAY OBSERVES THE MORAL COMMANDMENT INSCRIBED BY NATURE IN THE HUMAN HEART TO RENDER TO GOD AN OUTWARD, VISIBLE, PUBLIC, AND REGULAR WORSHIP "AS A SIGN OF HIS UNIVERSAL BENEFICENCE TO ALL."109 SUNDAY WORSHIP FULFILLS THE MORAL COMMAND OF THE OLD COVENANT, TAKING UP ITS RHYTHM AND SPIRIT IN THE WEEKLY CELEBRATION OF THE CREATOR AND REDEEMER OF HIS PEOPLE.
The Sunday Eucharist
2177
The Sunday celebration of the Lord's Day and his Eucharist is at the heart of the Church's life. "Sunday is the day on which the paschal mystery is celebrated in light of the apostolic tradition and
is to be observed as the FOREMOST HOLY DAY OF OBLIGATION IN THE UNIVERSAL CHURCH."110……
A DAY OF GRACE AND REST FROM WORK
2184 JUST AS GOD "RESTED ON THE SEVENTH DAY FROM ALL HIS WORK WHICH HE HAD DONE,"121 HUMAN LIFE HAS A RHYTHM OF WORK AND REST. THE INSTITUTION OF THE LORD'S DAY HELPS EVERYONE ENJOY ADEQUATE REST AND LEISURE TO CULTIVATE THEIR FAMILIAL, CULTURAL, SOCIAL, AND RELIGIOUS LIVES.122
2185
On Sundays and other holy days of obligation (note this is not a reference to the Sabbath see next post for the Catholic definition of holy days of obligation), the faithful are to refrain from engaging in work or activities that hinder the worship owed to God, the joy proper to the Lord's Day, the performance of the works of mercy, and the appropriate relaxation of mind and body.123 Family needs or important social service can legitimately excuse from the obligation of Sunday rest. The faithful should see to it that legitimate excuses do not lead to habits prejudicial to religion, family life, and health.
The charity of truth seeks holy leisure- the necessity of charity accepts just work.124
2186 Those Christians who have leisure should be mindful of their brethren who have the same needs and the same rights, yet cannot rest from work because of poverty and misery. Sunday is traditionally consecrated by Christian piety to good works and humble service of the sick, the infirm, and the elderly. Christians will also sanctify Sunday by devoting time and care to their families and relatives, often difficult to do on other days of the week. Sunday is a time for reflection, silence, cultivation of the mind, and meditation which furthers the growth of the Christian interior life.
2187 Sanctifying Sundays and holy days requires a common effort. Every Christian should avoid making unnecessary demands on others that would hinder them from observing the Lord's Day. Traditional activities (sport, restaurants, etc.), and social necessities (public services, etc.), require some people to work on Sundays, but everyone should still take care to set aside sufficient time for leisure. With temperance and charity the faithful will see to it that they avoid the excesses and violence sometimes associated with popular leisure activities. In spite of economic constraints, public authorities should ensure citizens a time intended for rest and divine worship. Employers have a similar obligation toward their employees.
2188 In respecting religious liberty and the common good of all, Christians should seek recognition of Sundays and the Church's holy days as legal holidays. They have to give everyone a public example of prayer, respect, and joy and defend their traditions as a precious contribution to the spiritual life of society. If a country's legislation or other reasons require work on Sunday, the day should nevertheless be lived as the day of our deliverance which lets us share in this "festal gathering," this "assembly of the firstborn who are enrolled in heaven."125
IN BRIEF
2189 "Observe the sabbath day, to keep it holy" (Deut 5:12). "The seventh day is a sabbath of solemn rest, holy to the Lord" (Ex 31:15).
2190
THE SABBATH, WHICH REPRESENTED THE COMPLETION OF THE FIRST CREATION, HAS BEEN REPLACED BY SUNDAY WHICH RECALLS THE NEW CREATION INAUGURATED BY THE RESURRECTION OF CHRIST.
2191 The Church celebrates the day of Christ's Resurrection on the "eighth day," Sunday, which is rightly called the Lord's Day (cf. SC 106).
2192 "
SUNDAY . . . IS TO BE OBSERVED AS THE FOREMOST HOLY DAY OF OBLIGATION (see next post on the definition of what that Holy days of obligation are) IN THE UNIVERSAL CHURCH" (CIC, can. 1246 § 1). "On Sundays and other holy days of obligation the faithful are bound to participate in the Mass" (CIC, can. 1247).
2193 "
ON SUNDAYS AND OTHER HOLY DAYS OF OBLIGATION (see next post on the definition of what that Holy days of obligation are) THE FAITHFUL ARE BOUND . . . TO ABSTAIN FROM THOSE LABORS AND BUSINESS CONCERNS WHICH IMPEDE THE WORSHIP TO BE RENDERED TO GOD, THE JOY WHICH IS PROPER TO THE LORD'S DAY, OR THE PROPER RELAXATION OF MIND AND BODY" (CIC, can. 1247).
2194 The institution of Sunday helps all "to be allowed sufficient rest and leisure to cultivate their amilial, cultural, social, and religious lives" (GS 67 § 3).
2195 Every Christian should avoid making unnecessary demands on others that would hinder them from observing the Lord's Day.
90 Ex 20:8-10; cf. Deut 5:12-15.
91 Mk 2:27-28.
92 Ex 31:15.
93 Ex 20:11.
94 Deut 5:15.
95 Cf. Ex 31:16.
96 Ex 31:17; cf. 23:12.
97 Cf. Neh 13:15-22; 2 Chr 36:21.
98 Cf. Mk 1:21; Jn 9:16.
99 Mk 2:27.
100 Cf. Mk 3:4.
101 Cf. Mt 12:5; Jn 7:23.
102 Mk 2:28.
103 Ps 118:24.
104 Cf. Mt 28:1; Mk 16:2; Lk 24:1; Jn 20:1.
105 Cf. Mk 16:1; Mt 28:1.
106 St. Justin, I Apol. 67G 6,429 and 432.
107 Cf. 1 Cor 10:11.
108 St. Ignatius of Antioch, Ad Magn. 9,1:SCh 10,88.
109 St. Thomas Aquinas, STh II-II,122,4.
110 CIC, can. 1246 § 1.
111 CIC, can. 1246 § 2:
"The conference of bishops can abolish certain holy days of obligation or transfer them to a Sunday with prior approval of the Apostolic See."
112 Cf. Acts 2:42-46; 1 Cor 11:17.
113 Heb 10:25.
114 Sermo de die dominica 2 et 6G 86/1,416C and 421C.
115 CIC, can. 515 § 1.
116 St. John Chrysostom, De incomprehensibili 3,6G 48,725.
117 CIC, can. 1247.
118 CIC, can. 1248 § 1.
119 Cf. CIC, can. 1245.
120 CIC, can. 1248 § 2.
121 Gen 2:2.
122 Cf. GS 67 § 3.
123 Cf. CIC, can. 120.
124 St. Augustine, De civ. Dei 19,19L 41,647.
125 Heb 12:22-23.
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Yep, seems it is not saying what you are claiming here. According to the Catechism and the teachings of the Roman Catholic Church SUNDAY REPLACES GOD'S SABBATH commandment of the 10 commandments.
Hope this helps