The author identifies himself as Paul, an apostle of Christ Jesus. Paul defends his use of the title on the basis of his call on the Damascus road (Ac 9:1-16), arguing in Gal 1:11-17 that he possesses apostolic authority, not by the vote of men, but by the will of God. In 3:1-8 and elsewhere (Ac 22:21; Gal 2:7), Paul notes that his calling is primarily to Gentiles, who make up a large portion of the group to whom this letter is directed.
The epistle was penned to instruct, edify, and encourage the saints . . . the faithful in Christ Jesus. Touched by the Holy Spirit, they are among God's new people, part of the new community formed by the Lord himself. Saints are not “holier-than-thou” people. They are those who have entered into a covenant with God through belief in Jesus as Messiah and Lord. In that relationship they continue to be beset by every human problem and trouble, but they are faithful in Christ Jesus. Having faith in Jesus as God's condition for their salvation, they remain committed to their faith in spite of earthly problems and struggles. In the biblical sense of the word, saints are holy ones (hagioi) because they belong to the God who is holy (hagios) and are sealed by God's Holy Spirit.
“Grace” and “peace” are fairly uniform elements of early Christian greetings. To “peace” (shalom), the typical Jewish greeting, believers in Jesus added “grace” (charis), aware of the unmerited favor bestowed on them through Jesus, the Father's gracious gift. Grace suggests that God has made himself and his unlimited resources available. Therefore, believers can be at peace, free from anxiety, secure in the knowledge that by grace they can and will endure.