God Is Faithful and Without Any Iniquity: The Canticle of Moses, Faithful and Just to Forgive
Old Testament: Deuteronomy 32:4
The works of God are perfect, and all his ways are judgments: God is faithful and without any iniquity, he is just and right.
Old Testament, also: Exodus 34:6-7
And when he passed before him, he said: O the Lord, the Lord God, merciful and gracious, patient and of much compassion, and true, Who keepest mercy unto thousands: who takest away iniquity, and wickedness, and sin, and no man of himself is innocent before thee. Who renderest the iniquity of the fathers to the children, and to the grandchildren, unto the third and fourth generation.
New Testament: Apocalypse 15:3-4; 1 John 1:9; Apocalypse 19:11
And singing the canticle of Moses, the servant of God, and the canticle of the Lamb, saying: Great and wonderful are thy works, O Lord God Almighty; just and true are thy ways, O King of ages. Who shall not fear thee, O Lord, and magnify thy name? For thou only art holy: for all nations shall come, and shall adore in thy sight, because thy judgments are manifest. ... If we confess our sins, he is faithful and just, to forgive us our sins, and to cleanse us from all iniquity. ... And I saw heaven opened, and behold a white horse; and he that sat upon him was called faithful and true, and with justice doth he judge and fight.
The connection
At the end of his life Moses gives Israel a song to keep, and after its opening call to heaven and earth he gives one line about who God is: "The works of God are perfect, and all his ways are judgments: God is faithful and without any iniquity, he is just and right." Faithful, just, without iniquity; His ways are judgments. The rest of the canticle is Israel's unfaithfulness set against that one fact. The Apocalypse hears the song again. Beside the sea of glass the victors sing "the canticle of Moses, the servant of God, and the canticle of the Lamb", and what they sing is that line of Moses: "just and true are thy ways, O King of ages ... For thou only art holy." In the Greek the words are the ones the Septuagint gives Moses: ways, just, true, holy. The song Moses taught a people on the edge of the promised land is the song of the saved on the far shore. St John uses the same line twice more, once for each coming. To sinners now: "If we confess our sins, he is faithful and just, to forgive us our sins, and to cleanse us from all iniquity." Faithful, just, iniquity: three of the canticle's words in one sentence, and the fact that God is without iniquity is turned into the promise that He will cleanse it out of us. And at the end: "he that sat upon him was called faithful and true, and with justice doth he judge." The faithfulness that judges is the faithfulness that forgives. The God Moses praised as without iniquity does not forgive by pretending sin away; He is just, and He has bound Himself by a promise, and He keeps it. That is why the Lord who revealed Himself to Moses as "true" and as the one "who takest away iniquity" can be trusted by the one who confesses.
Moral sense
Confession does not rest on how sorry we feel or how well we say it, but on who God is. He is faithful and just to forgive: not might, but is. The soul that has confessed with a contrite heart and still doubts has trusted its own feelings over His faithfulness. Moses's line at 32:4 is the answer to that doubt: God is faithful and without any iniquity, and a promise from Him is kept.
Anagogical sense
Moses's canticle ends in the Apocalypse sung by those who stand beside the sea of glass, and the King they praise is the one who comes out of heaven opened called Faithful and True. The forgiveness given in the confessional and the judgment given at the end are the same faithfulness seen at two moments. Those who were cleansed from all iniquity will sing, at last, that His ways were just and true all along.
The Fathers
St Cyprian, On the Lord's Prayer 22: "Therefore he said that the Lord was faithful to forgive sins, keeping the faith of His promise; because He who taught us to pray for our debts and sins, has promised that His fatherly mercy and pardon shall follow."
Warrant
Scriptural because Apocalypse 15:3 names the song, "the canticle of Moses, the servant of God", and sings its words. Moses sang two canticles, Exodus 15 and Deuteronomy 32 (called "this canticle" at 31:30 and 32:44); the words sung in the Apocalypse are those of Deuteronomy 32:4, not Exodus 15. Checked in the originals: the Septuagint of Deuteronomy 32:4 reads true (alethina), ways (hodoi), judgments (kriseis), faithful (pistos), no iniquity (adikia), just (dikaios) and holy (hosios), and Apocalypse 15:3-4 has just and true ways (dikaiai kai alethinai hai hodoi) and "only holy" (hosios). 1 John 1:9 has three of the same words, faithful (pistos), just (dikaios) and iniquity (adikia), and Apocalypse 19:11 has faithful and true (pistos, alethinos) with justice (dikaiosyne) and judging (krinei). Joining 1 John 1:9 and Apocalypse 19:11 to the canticle is the entry's own, resting on those shared words; no Father in the site's corpora was found joining them to Deuteronomy 32:4, and a search was made. St Cyprian (On the Lord's Prayer 22) reads 1 John 1:9 as God keeping His promise, which the entry follows. Exodus 34:6-7 is added for the Lord named true and as taking away iniquity.
Catechism of the Catholic Church, paragraph 214.
The verses
Deuteronomy 32:4 · Exodus 34:6 · Exodus 34:7 · Apocalypse 15:3 · Apocalypse 15:4 · 1 John 1:9 · Apocalypse 19:11
