This post is part of an ongoing series on Forgiveness in the Gospel of Matthew.
We must also unearth some of our parable’s literary sources, those materials which stand behind this narrative and help shed light on how Jesus and Matthew’s audiences would have understood this story. The vast majority of scholars attribute at least the kernel of this story to the Historical Jesus, although most find evidence of (sometimes significant) changes as well. Three realms of literary material are often thought to influence the final form of Matthew 18:21-35: redactional sources, Old Testament writings, and first-century influences.
The most common redactional option suggested for this parable is that Matthew drew upon a brief saying found in Q (typically located in 18:21-22 and also used in Luke 17:1-4), then expanded upon and reinterpreted that tradition for his own community. In this line of thinking, the parable itself is either an expansion (or embellishment) of the authentic Jesus saying or Matthew’s own literary creation. The other primary redactional option is that Matthew built upon oral tradition or catechetical materials in his use of this parable. For example, Luz writes, “I am on the opinion, therefore, that Matthew put into written form a story that previously had been transmitted orally….” Similarly, Meier posits that, “M material no doubt grew in liturgical and catechetical activity of the Church over decades and was the living Sitz im Leben in which Mark and Q were understood long before the sources were brought together by Matthew. M, therefore, should be viewed as a dynamic oral tradition rather than some sort of primitive document.”
A number of Old Testament echoes have been located in the Parable of the Unforgiving Servant. Most widely recognized is Leviticus 19:17’s command to not hate one’s brother from the heart, which apparently informs at least v. 35. Scholars have posited several different passages in Sirach as influences on this parable. Sirach 19:3-17 likely forms a general “wisdom tradition” background for reproving friends when necessary. Even more central to this parable is Isaac Mbabazi’s investigation of the themes and terminology of Sirach 28:1-7, which contains themes of God’s judgment on those who refuse to practice mercy and forgiveness and the notion that human activity may influence the divine. Although literary echoes are famously difficult to determine with any meaningful degree of certainty, it does seem that this parable builds from themes present in Leviticus 19 and Sirach 28.
Although not necessarily written materials, several first-century influences are also thought to have shaped (or paralleled) Matthew 18:21-35. The most obvious of these involves the teachings and community regulations of first-century Judaisms. The Pharisaical tradition had long wrestled with questions concerning forgiveness and apparently come to the conclusion that three instances of forgiveness was sufficient for the same sin; perhaps Peter had this dialogue in the back of his mind when asking Jesus about the ‘seven times’ he should forgive his brother. Other portions of Matthew 18 parallel quite closely other Second Temple period teachings on receiving brothers found in sin, suggesting that Jesus’ conversations about the church stood in some continuity with other Jewish interpreters of the period. Perhaps the closest parallel to this portion of Matthew comes in the Community Rule of Qumran, which speaks of not hating from the heart in order to not incur guilt. A final first-century influence is the general context of Greco-Roman economics, wherein hearers of this parable would have been expected to understand the amounts of money being demanded and the legal expectations of loans.
For the purposes of this project, I am inclined to proceed to consideration of the meaning of Matthew 18:21-35 on the bases 1) that the parable originated with the Historical Jesus, who was reflecting on Old Testament themes; 2) that the parable circulated in oral form until Matthew wrote the account down and added minor literary adjustments; and 3) that for Matthew and Jesus, the parable was useful not only for community formation but also stood in conversation with contemporary Second Temple Jewish discussions. This literary context in mind, we now turn to consideration of the meaning of Matthew 18:21-35.
 Lambrecht, 58-63.
 Davies and Allison, 781. Thompson, 237. Harrington, 270. Konradt, 132. For a helpful discussion of the status questionis of the Synoptic Problem, see David Alan Black and David R. Beck (eds.), Rethinking the Synoptic Problem (Grand Rapids: Baker Academic, 2001).
 de Boer, 225-31. “If such embellishment of the figures can be attributed to Matthew in the parable of the Talents [cx. Matt. 25:16-28 and Luke 19:11-27], the possibility that he has also embellished the amount of the servant’s debts in the parable of the Unforgiving Servant is strengthened.” (de Boer, 228) See also S.H. Brooks, Matthew’s Community: The Evidence of His Special Sayings Material (Sheffield: JSOT, 1987).
 Luz, 469. On vv. 21-23 see Davies and Allison, 781.
 Meier, 623. See also Johnson, 190.
 Davies and Allison, 786. Lev. 19.15-18. Compare also Prov. 10.18; 26.24-5. See also Bronn’s argument on the use of Genesis 45.1-5 in v.35 (William R. Bronn, “Forgiveness in ‘My Brothers’ of Matthew 28:10 and Its Significance for the Matthean Climax (28:16-20),” BTB 40.4 : 210-213).
 Illian, 446.
 Isaac Kahwa Mbabazi, “The Jewish Background to Interpersonal Forgiveness in Matthew,” African Journal of Evangelical Theology 30.1 (2011): 15-6. See also Sirach 5.4-7, 17.25-32, 18.8-14, and 28.1-46. See also David J. Reimer, “Stories of Forgiveness: Narrative Ethics and the Old Testament,” 359-378 in Reflection and Refraction: Studies in Biblical Historiography in Honour of A. Graeme Auld (eds. R. Rezetko, T.H. Lim and W.B. Aucker. Leiden: Brill, 2007), 359-78.
 Donald A. Hagner, Matthew 14-28 (Dallas: Word Books, 1995), 537. Cx. b. Yoma 86b-87a and m. Yoma 8:9.
 Compare 18.15-7 with CD IX, 2-8; 1QS V, 24-VI, 1; Testament of the Twelve Patriarchs, T. Gad 4:2-3, 6:37. Geza Vermes, The Complete Dead Sea Scrolls in English (New York: Penguin Press, 1997).
 “They shall rebuke one another in truth, humility, and charity. Let no man address his companion with anger, or ill-temper, or obduracy, or with envy prompted by the spirit of wickedness. Let him not hate him [because of his uncircumcised] heart, but let him rebuke him on the very same day lest he incur guilt because of him. And furthermore, let not man accuse his companion before the Congregation without having admonished him in the presence of witnesses.” 1QS5.25-6.1. Vermes, 105.
 Scott, 433. See also J. Duncan M. Derrett, Law in the New Testament (London: Darton, Longman & Todd, 1970).