Keeping the Sabbath day is a qualifier for the celestial kingdom

“The law of the Sabbath is so basic, so fundamental, that the Lord Jehovah named it as number four in the Ten Commandments themselves. The first three commandments call upon men to worship the Lord and reverence his great and holy name. The fourth gives us the Sabbath day as the weekly occasion on which we perfect our worship and put ourselves in tune to the full with Him by whom all things are. “It is in no sense an exaggeration nor does it overstate the fact one whit to say that any person who keeps the Sabbath, according to the revealed pattern, will be saved in the celestial kingdom. The Sabbath is a day of worship; the requirement to rest from our labors, to do no servile work therein, is simply an incident to the real purpose of the day. Vital as it is to refrain from the toil and to turn away from temporalities, these requirements are for the purpose of putting men in a position to do what should be done on the Sabbath, that is, to worship the Father in the name of the Son, to worship him in Spirit and in truth. True worship includes keeping the commandments, and those who devote their Sabbaths to true and proper worship obtain the encouragement that leads to full obedience.” – Bruce R. McConkie, “The Promised Messiah” pp. 390-391