I think it's important to point out that the traditions which Paul is refering to in the scriptures you quoted are the "traditions" and celebrations that were given us in the Old Testament, and these things are not found in Christian churches today.  In fact they have been wholly and completely replaced with such things as Christmas, Easter, Birthdays etc... the Passover, Feast of Tabernacles, Yom Kippur etc now seem to be recognized by the masses as "Jewish" holidays instead of the rich "traditions" of a culture given to us by the Most High... where in fact our bible tells us we are to stay far away from the traditions and practices of this world, we have "christianized" them and thus feel they are therefore permissable. 

I do believe that celebrating pagan traditions is spiritual adultery.  I also believe that what we ought to be celebrating are the festivals that were given to us in the Old Testament... the heritage we were given by the Father.  Because if we are not celebrating those things that he laid out for us, and not living according to his will which is laid out in the old testament, and instead of that are celebrating gluttony and paganism... where exactly does that leave us spiritually? 

I think that he who believes he has all knowledge, really has nothing at all... and that too is scriptural... we are to continue to search, and to work out our salvation with fear and trembling. 

oh my... the everlasing debate.  The etymology of the word Sabbath... according to www.etymonline.com

O.E. sabat "Saturday," observed by the Jews as a day of rest, from L. sabbatum, from Gk. sabbaton, from Heb. shabbath, prop. "day of rest," from shabath "he rested." The Babylonians regarded seventh days as unlucky, and avoided certain activities then; the Jewish observance may have begun as a similar custom. From the seventh day of the week, it began to be applied c.1410 to the first day (Sunday), a change completed during the Reformation. The original meaning is preserved in Sp. Sabado, It. Sabbato, and other languages' names for "Saturday." Hung. szombat, Rus. simbata, Fr. samedi, Ger. Samstag "Saturday" are from V.L. sambatum, from Gk. *sambaton, a vulgar nasalized variant of sabbaton.

One man considers one day more sacred than another, another man considers every day alike.  Each one should be fully convinced in his own mind.  He who regards one day as special, does so to the Lord.  Romans 14:5-6

Does that mean we can celebrate any day as the sabbath?  NO!!  We celebrate the Lord's day... not Sunday which is a sacred day to the Sun God... hence SUN day... Read what it says in the above section about the Babylonians... THEY CHANGED THE DAY PEOPLE!!!  BECAUSE THEY WERE SUPERSTITIOUS!!!!