1 John 2:2

2:2 and he himself is the atoning sacrifice ¹  for our sins, and not only for our sins but also for the whole world. ² 

1 John 2:4

2:4 The one who says “I have come to know God” ³  and yet does not keep his commandments is a liar, and the truth is not in such a person.

[2:2]  ¹ tn A suitable English translation for this word (ἱλασμός, Jilasmos) is a difficult and even controversial problem. “Expiation,” “propitiation,” and “atonement” have all been suggested. L. Morris, in a study that has become central to discussions of this topic (The Apostolic Preaching of the Cross, 140), sees as an integral part of the meaning of the word (as in the other words in the ἱλάσκομαι [Jilaskomai] group) the idea of turning away the divine wrath, suggesting that “propitiation” is the closest English equivalent. It is certainly possible to see an averting of divine wrath in this context, where the sins of believers are in view and Jesus is said to be acting as Advocate on behalf of believers. R. E. Brown’s point (Epistles of John [AB], 220-21), that it is essentially cleansing from sin which is in view here and in the other use of the word in 4:10, is well taken, but the two connotations (averting wrath and cleansing) are not mutually exclusive and it is unlikely that the propitiatory aspect of Jesus’ work should be ruled out entirely in the usage in 2:2. Nevertheless, the English word “propitiation” is too technical to communicate to many modern readers, and a term like “atoning sacrifice” (given by Webster’s New International Dictionary as a definition of “propitiation”) is more appropriate here. Another term, “satisfaction,” might also convey the idea, but “satisfaction” in Roman Catholic theology is a technical term for the performance of the penance imposed by the priest on a penitent.

[2:2]  ² tn Many translations supply an understood repetition of the word “sins” here, thus: “but also for the sins of the whole world.”

[2:4]  ³ tn Grk “know him.” See the note on the phrase “know God” in 1 John 2:3 for explanation.