Arthur Peake's Commentary on the Bible
2 Samuel 22 - Introduction
1 Samuel 21-24. These Chapter s form an appendix of material from various sources. One of the editors, perhaps the one to whom the book substantially owes its present form, seems to have met with difficulties in an attempted rearrangement of some of the material; finding no other convenient place for 2 Samuel 21:1 Samuel 24, he added them at the end, as a kind of appendix. He or someone else inserted between them the catalogue of heroes (2 Samuel 21:15; 2 Samuel 23:8); later on someone inserted 1 Samuel 22 and 1 Samuel 23:8 in the middle of the catalogue. The reader must remember that ancient editors and scribes had no assistance from divisions of Chapter s and verses or headings; and that only the consonants were written, so that it was not possible to see at a glance where was the most suitable place for an addition.
The proper continuation of ch. 20 is 1 Kings 1.