Growth: Peter continues the imagery of birth (1:23, “born again”) and its natural aftereffect: growth (“grow”).[1] We were spiritually born to grow. Even as infants are meant to grow up, so souls were born again to mature. Spiritual growth is as natural and necessary as a baby’s physical development.[2] Peter describes our birth[3] as the putting off of our former vices,[4] the purification in which we tasted of the Lord’s kindness. The great obstacle to spiritual life is sin. So long as we cling onto sin, the Word is disgusting, and so life impossible. The Lord kindly drew us out of sin and gave us new life (1:14-15; Rom. 6:4).
Longing: Peter gives a command regarding our desires.[5] Even as a babe craves his mother’s milk, so it is natural for the repentant to manifest a desire for the Word that is eager and frequent (like a newborn). This is the command that we hunger for the Word of God in this fashion. The Word is a “delight” (Ps. 1:2) and “more desirable than gold” and “sweeter than honey” (Ps. 19:10), because it is the only source of untainted and “pure” spiritual nourishment. The Word is “perfect… sure… right… clean… true… righteous” (Ps. 19:7-9). It is “a lamp unto our feet” (Ps. 119:105). It tells of God’s holiness, His love for sinners, His call to repentance, justification through Jesus’ blood, etc. It wises us up to hate sin and shun evil. It is the book that nourishes and sustains our souls until we are safely home in heaven (“into salvation”). Eat and live!
[1] This is the import of “Therefore [oun (οὖν)]” of 2:1. The natural consequence of birth (1:23) is that we grow.
[2] The saved mature (Col. 1:28; Gal. 4:19-20; Eph. 4:13-15); they do not remain in infancy (Heb. 6:1-9).
[3] The prerequisite to Christian love is the putting aside of evil (2:1) even as repentance was in 1:22.
[4] These were a part of “the former lusts … in your ignorance” (1:14) and the putting off of them an aspect of the “obedience to the truth” (1:22) and the call to repentance an aspect of the Lord’s kindness (Rom. 2:4).
[5] e-pi-po-the-ō (ἐπιποθέω) describes a deep longing/yearning (cf. 2 Cor. 5:2; 1 Thess. 3:6; James 4:5).