For you were continually straying like sheep, but now you have returned to the Shepherd and Guardian of your souls. (2:25)
As he concluded this passage, Peter once more alluded to Isaiah 53, “All of us like sheep have gone astray, each of us has turned to his own way; but the Lord has caused the iniquity of us all to fall on Him” (v. 6). If God had not determined that all believers’ sins should fall on Jesus, there would be no shepherd to bring God’s flock into the fold.
The phrase were continually straying like sheep describes by analogy the wayward, purposeless, dangerous, and helpless wandering of lost sinners, whom Jesus described as “sheep without a shepherd” (Matt. 9:36). The verb rendered have returned (epestraphēte) carries the connotation of repentance, a turning from sin and in faith a turning toward Jesus Christ. But Peter’s readers had trusted in Christ’s substitutionary death and turned to Him for salvation. Like the prodigal son in Luke 15:11–32, they had turned away from the misery of their former sinful life (cf. Eph. 2:1–7; 4:17–24; Col. 3:1–7; 1 Thess. 1:2–10) and received new life in Christ (cf. Eph. 5:15–21; Col. 3:8–17; 1 Thess. 2:13–14). All who are saved come under the perfect care, provision, and protection of the Shepherd and Guardian of their souls.
The analogy of God as shepherd is a familiar and rich theme in Scripture (cf. 5:4; Ps. 23:1; Ezek. 34:23–24; 37:24). Jesus identified Himself as God when He took the divine title and named Himself the “good shepherd” (John 10:11, 14). Shepherd is an apt title for the Savior since it conveys His role as feeder, leader, protector, cleanser, and restorer of His flock. And believers as sheep is also an apt analogy because sheep are stupid, gullible (a sheep called the “Judas sheep” in modern times leads the other sheep to slaughter), dirty (the lanolin in sheep’s wool collects all kinds of dirt), and defenseless (they have no natural defensive capabilities). (See the discussion of shepherding in chapter 23 of this volume.)
The term Guardian (episkopos) serves as a synonym, another term describing Jesus’ care for His flock. It is the word usually translated “bishop” or “overseer,” which along with Shepherd also describes the responsibilities of the pastor or elder (cf. 1 Tim. 3:1–7; Titus 1:5–9). Later in this letter, Peter uses both root words when he exhorts elders to “shepherd the flock of God … exercising oversight not under compulsion, but voluntarily, according to the will of God” (5:2). By His death and resurrection for His flock, the Lord has become the Shepherd and Guardian of their eternal souls. In suffering, He became their example, their substitute, and their shepherd.
MacArthur New Testament Commentary