Saved by Grace is definitely in Catholic teaching.
But you really have to dig for it. It is buried beneath
two millennia of ceremony and process and misguided tradition.
My parents believed that you might not be saved if you didn’t make Mass on all of the First Fridays. That is not actually Church teaching, but they sure didn’t work very hard to disabuse anyone of the notion.
I’m a miserable sinner who is a practicing Catholic with a fairly good understanding of the Catholic faith. Christ’s death and resurrection opened the gates of Paradise to every human being...potentially. So, now that the gates of Paradise are open, how does anyone get that hand-stamp to get admitted? Well, if faith in Jesus Christ gets you the hand stamp, then do all Christians who believe in Jesus get into Heaven, regardless of the sins they commit, even if they are not sorry for their sins? What about Jews who love God, but we’re taught that Jesus was a; fraud? Have they no hope for Heaven? It is very complicated. I believe that Catholicism teaches that Jesus opened the gates of Paradise; that God grants to everyone in the world the grace sufficient to be saved; that we as humans cannot know how faith and works act to enable us to accept the grace we need to accept to be saved.
I’m a miserable sinner who is a practicing Catholic with a fairly good understanding of the Catholic faith. Christ’s death and resurrection opened the gates of Paradise to every human being...potentially. So, now that the gates of Paradise are open, how does anyone get that hand-stamp to get admitted? Well, if faith in Jesus Christ gets you the hand stamp, then do all Christians who believe in Jesus get into Heaven, regardless of the sins they commit, even if they are not sorry for their sins? What about Jews who love God, but we’re taught that Jesus was a; fraud? Have they no hope for Heaven? It is very complicated. I believe that Catholicism teaches that Jesus opened the gates of Paradise; that God grants to everyone in the world the grace sufficient to be saved; that we as humans cannot know how faith and works act to enable us to accept the grace we need to accept to be saved.
Actually the RCC does teach something along these lines.
Canon 1247
On Sundays and other holy days of obligation the faithful are bound to participate in the Mass; they are also 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.
Canon 1248
1. The precept of participating in the Mass is satisfied by assistance at a Mass which is celebrated anywhere in a Catholic rite either on the holy day or on the evening of the preceding day.
2. If because of lack of a sacred minister or for other grave cause participation in the celebration of the Eucharist is impossible, it is specially recommended that the faithful take part in the liturgy of the word if it is celebrated in the parish church or in another sacred place according to the prescriptions of the diocesan bishop, or engage in prayer for an appropriate amount of time personally or in a family or, as occasion offers, in groups of families.
Since a "grave cause" is needed to excuse one from this obligation it would be a serious or mortal sin to willfully skip Mass on Sunday or a Holy Day of Obligation, as the Church has always taught. Reasons such as the necessity to work to support one's family, child care, personal sickness or the care of the sick, necessary travel etc. would excuse a person on a particular occasions. Those who have continuing reason to be excused should consult their pastor.
https://www.ewtn.com/expert/answers/sunday_mass.htm