1 Peter 1:22 → Leviticus 19:18

Peter's exhortation — "love one another deeply, from a pure heart" (1:22) — is a covenantal echo of Leviticus 19:18, the more striking because it stands in a chapter saturated with the Holiness Code: just six verses earlier Peter quotes Lev 19:2, "Be holy, because I am holy" (1:16). Having grounded the church's identity in the holiness command of Leviticus 19, Peter then draws out its interpersonal climax — the love-command of the same chapter — so that Lev 19:2 (be holy) and Lev 19:18 (love your neighbor) are reconnected in their original Levitical pairing. The newness is in the ground: this love springs from souls "purified by obedience to the truth" and from new birth "through the living and enduring word of God" (1:22-23), so that neighbor-love is no longer commanded of a stony heart but produced from a regenerated one. This is the new-covenant fulfillment of Lev 19:18 — the law written on the heart (Jer 31:33) issuing in deep, sincere love. The telos is secured by the surrounding context: this love flows from a people who "were redeemed... with the precious blood of Christ, a lamb without blemish" (1:18-19), whose "faith and hope are in God" (1:21). Brotherly love "from a pure heart" is therefore the overflow of a redeemed and rejoicing heart, not anxious moral effort — the love Lev 19:18 always required, now made the glad fruit of those purified and reborn by the gospel.