The concept of taking Christ's name upon oneself is mentioned all over the Book of Mormon. What exactly does this mean? I thought about times we "take" someone else's name upon us. For instance - when you adopt someone, s/he takes on your surname. When a woman marries, usually (but not always) she takes on her husband's surname. Taking on someone's surname can be seen as a symbol of linking or joining two people together.
Here are four ways you take Christ's name upon yourself.
Joining His Church
You take Christ's name upon yourself by becoming a member of His church - a Christian.
"...And it came to pass that whosoever were desirous to take upon them the name of Christ, or of God, they did join the churches of God." Mosiah 25:23
Becoming His Child
You take His name upon yourself when you become one of His children through spiritual rebirth (similar to the adoption example above - taking on your father's surname).
"And now, because of the covenant which ye have made ye shall be called the children of Christ, his sons, and his daughters; for behold, this day he hath spiritually begotten you; for ye say that your hearts are changed through faith on his name; therefore, ye are born of him and have become his sons and his daughters." Mosiah 5:7
Emulating His Character
In the Old Testament, the Hebrew word "shm" is usually translated as "name," but in ancient Hebrew culture, it meant far more than just a way to identify someone. The Ancient Hebrew Lexicon (AHL) defines "ShM" as breath: "The breath of a man is character, what makes one what he is." (link) So another way you take Christ's name upon yourself is by emulating His "shm," or character. This involves doing what He would do, saying what He would say, and serving as He would serve.
Saving and Delivering Others
The AHL definition of "ShM" continues: "The name of an individual is more than an identifier but descriptive of his character or breath." So a name represented character, but the definition of the name also was supposed to describe that person's character. The meaning of Jesus's name, Yeshua, is "deliverer or savior." You also take His "shm" upon you when you submit your will and desires to His, uniting with Him to save and deliver others.