What does 1 Peter 2:2 mean?

Having set aside unloving attitudes and actions (1 Peter 2:1), Peter writes that we must now crave something other than our own selfish gratification. Notice that Christians are being commanded about what to want. We have to be told what to crave because this appetite doesn't always come to us naturally. This "pure spiritual milk" is exactly what we need: the stuff that meets our deepest needs. In fact, we do not always long for it.

How do we develop this appetite? We must start drinking. Newborn infants will sometimes reject the very milk they are crying for, at first, until they get a taste of it. And then they guzzle hungrily. In Peter's metaphor here, all Christians are to crave this milk like newborns, even the mature believers. This is not to be confused with Paul's separate metaphor of milk and meat in 1 Corinthians 3:1–3. No Christian reaches the point on this side of eternity where spiritual growth is completed.

So what is this "pure spiritual milk" we need to hunger for? The word "pure" simply means undiluted or uncontaminated. The word used to describe this milk in the original Greek is logikon, which could also mean "rational or reasonable." More importantly, it shares a root with the word logos, "the word." This phrase is sometimes translated as "pure milk of the word," as in the NASB. "The word / Word of God" can refer both to His revealed word in Scripture, including the message of the gospel—and to Christ Himself, the Word made flesh (John 1:14).

So this command means we must learn to crave the undiluted word of God, as a newborn craves milk. By drinking this milk, taking in God's word, drawing close to Christ, believers will continue to grow up in our salvation. Peter has already made clear that God has secured our salvation (1 Peter 1:3–5), that we are being saved (1 Peter 1:9), and that we will receive salvation fully when Christ is revealed (1 Peter 1:5). For now, taking in the "milk" of God's Word is the intended path of spiritual growth.