The angel Gabriel gives the reason why Christ should bear this name when he announces to Joseph, Matt. 1:21: “Thou shalt call His name Jesus: for He shall save His people from their sins.” This name we must study with diligence, and carefully remember that this Child is called Jesus because He is a Savior who delivers from the severest and greatest misery, namely, from sin, and not from the insignificant troubles and petty anxieties which this life has in store for this or that individual, and which can but affect our body, our possessions, or some other temporal matter. God has instituted other means by which such perplexities as these are solved or averted. He has given us rulers and authorities to protect and defend their subjects against lawlessness; He has appointed parents to support and to educate their children; He has given physicians to advise us and assist us in our bodily infirmities, etc. These, however, are all miserable helpers compared with Him who is a Savior and can save His people from sin. He who would possess this Child as his Savior, as Jesus, must ever remember that He is a Helper, not chiefly in the concerns of this life, which are otherwise provided for, as we have stated, but above all a Savior from sin and death unto eternal life. For where sin no longer rules, there death must also yield up his power. (Luther’s House Postil, Sermon for the 2^nd Sermon for New Year, Volume 1, p. 142-143)

This now is our King, the dear Lord Jesus Christ, and this is His kingdom and office. It deals not with golden crowns and kingdoms, or with great worldly pomp; no, but when we must die, and cannot retain this life any longer, then it is His office and work to deliver us from sin, death and the power of hell; and through the preaching of the gospel He announces to us that we shall certainly receive this gift or benefit from Him, so that when we are in trouble on account of our sins, or in danger of death, we can comfort ourselves by faith and say: Now help is afforded me through my dear King, Jesus Christ, the Just One and Savior; to this end He came, so lowly and poor, and suffered Himself to be nailed to the cross, that He might justify and sanctify me; in Himself He hath destroyed my sin and death, gives me His own righteousness and victory over death and hell, and gives me also His Holy Spirit, that I might have in my heart a sure seal and witness of His help. See now, whoever believes this as he hears it, and as it is preached in the gospel, he also has it. For to this end holy baptism was instituted by our Savior that He might clothe you with His righteousness, and that His holiness and innocence should be yours. For we are all poor sinners, but in baptism, and afterwards in our whole life, if we turn unto Christ, He comforts us, and says: Give me your sins and take my righteousness and holiness; let your death be taken from you, and put on my life. This is, properly speaking, the Lord Jesus’ government. For all His office and work is this, that He daily takes away our sin and death, and clothes us with His righteousness and life. (Luther’s House Postil, Sermon for the 1^st Sunday in Advent, Volume 1, p. 21)

Hence the Evangelist says, as already mentioned: “Tell ye the daughter of Zion.” And the prophet says: “Rejoice greatly, O daughter of Zion, behold thy King cometh unto thee,” as if he would say: This is told to you and God wishes to have it proclaimed to you, that you may find consolation in Him by faith, and be defended by such faith against doubt and despair on account of your unworthiness and sins. What is it that is told, and on account of which she is to rejoice? It is this: “Behold thy King cometh unto thee.” What kind of a king? A holy and just King, a Physician and Savior, or Helper, who would heal and save you. He would give His glory and righteousness to you, that you may be free from your sins; His life also He would lay down for you, that through His death you may be delivered from eternal death. Therefore be not offended at His lowly and humble form, but thank Him for it, and comfort yourself in Him. For all that He does and accomplishes in His coming, is done for your good; thus He would deliver you from your sins and from death, and justify and save you.  (Luther’s House Postil, Sermon for the 1^st Sunday in Advent, Volume 1, p. 20-21)