Rom 1:16 For I am not ashamed of the gospel of Christ: for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek.
Luk 2:11 For unto you is born this day in the city of David a Saviour, which is Christ the Lord.
Two great verses and two very powerful words. In Romans we have the word salvation and in Luke we have the word Saviour. We have an indication that there are those that need saving and there is one who saves. Let's look at these two words in the Greek.
First up is the word salvation in Romans. In the Greek the word is "σωτηρία" (sōtēria / so-tay-ree'-ah). This word is a noun meaning rescue or to bring into safety either physically or morally. Next is the word Saviour in Luke. In the Greek the word is "σωτήρ" (sōtēr / so-tare'). This word means deliverer.
It is not just the meanings of the words that are important but also their gender. Salvation is feminine (the weak vessel) and Saviour is masculine (the strong vessel). In other words a very strong one (Jesus Christ) has come to rescue the weak ones (the saints). You could also say that we are the damsel in distress that the hero has rescued. We see this same picture with Ruth where Boaz becomes her kinsman redeemer.
During Biblical times a wife found protection in marriage. Women who had no father or husband were much more likely to be assaulted and violated. Women in a marriage had a stronger one who would hide them from the evil.
Now apply this to ourselves, the saints. We are the weak; we were engulfed in the muck of sin, dead in sins, under the curse of the law, destined for hell and with no way of escape; but Christ himself, the strong arm of the Lord, reached down into the muck and brought us out, delivering us. Now we find ourselves under his protection. Protected from God's wrath on the day of judgment, protected from the evil one, protected from the evils of this world and even protected from submitting too and committing sin.
Paul takes this one step farther in Ephesians chapter 5. In verse 23 he says that Christ is the head of the Church and he is the saviour (the strong deliverer) of the body. Just as in biblical times marriage was a protection for the wife, so now is Christ the protector of his bride, the Local Church. Take a moment to read Eph. 5:22-33 and see how Christ has delivered his bride; you will also find that marriage is a picture of the relationship Christ has with his people.