This is the only verse in the Bible where our Savior is called "the Lord Christ." Actually, His three primary names ("Lord," "Jesus," and "Christ") are combined in eight different ways in the New Testament.
"Jesus" was His human name, speaking especially of His mission as suffering Savior. "Christ," equivalent to the Hebrew "Messiah" (meaning "anointed") speaks of His office as God's chosen King. As "Lord" He is sovereign Creator and ruler of the universe; victorious over all enemies, even death itself.
"Lord Christ" is the only one of the combination forms of His name which omits the human name. Apparently the reason is that, in this passage, the emphasis is altogether on His exalted position as sovereign Creator and eternal King and the seriousness of our service to Him.
Our service is to be rendered not to men--not even to the man Jesus in His perfect humanity--but to the Lord and the Christ--the Lord Christ, Creator of all things and King of kings. "Your labor is not in vain in the Lord" (I Corinthians 15:58) for He is "heir of all things" (Hebrews 1:2) and thus can dispense "the reward of the inheritance" to His faithful servants who are "joint-heirs with Christ" (Romans 8:17). The inheritance is ours because of our position in Christ; the reward is given for service for the Lord.
Because of whom we serve, whatever we do should be done heartily! This is the Greek word, psuches, usually translated "soul," or "life," as well as "heart." If there is anything we cannot in good conscience do with full heart to the Lord, then it should not be done at all. HMM