Adult Jewish males throughout the Empire paid an annual two-drachma tax, based on Exodus 30:13-16, for the upkeep of the Jerusalem temple (compare E. Sanders 1992:156). Even in Matthew's day, (probably) after the temple was destroyed, this tax remained important: after 70, the Romans required all Jewish people (including Jewish Christians maintaining allegiance to their Jewish heritage) to pay that tax to the Roman government (see CPJ 1:80-81; 2:119-36, 160-229; Hemer 1973; Carlebach 1975). For the sake of maintaining public identification with their Jewish heritage, Jewish Christians should join non-Christian Jews in paying the tax. The principle is that we must sometimes engage in otherwise unprofitable pursuits for the sake of upholding our witness as citizens of the communities where God has placed us.
Jesus Cares About Our Social Obligations (17:24-26)
Like a good prophet, Jesus knows in advance Peter's question (17:25). He also does not regard the poll tax as binding on himself or Peter (vv. 25-26), but recognizes that the tax collectors may (v. 24). He thus does not rebuke Peter for committing him (v. 25); he wishes to avoid unnecessary cause for misunderstandings (v. 27) that might turn people away from his gospel unnecessarily (compare 5:29-30; 13:41; 16:23; 18:6). Jesus has offended (literally "caused to stumble") members of the religious establishment before (15:12-14), but this is an unnecessary "stumbling block" because it addresses one's own rights rather than the truth of God's kingdom (18:6).
Surrendering "Rights" for the Sake of the Gospel (17:27)
Jesus' point here is similar to Paul's point in 1 Corinthians 9 and 10:29-33: one should sacrifice one's own privileges for the sake of the gospel. Head or poll taxes normally listed specific exceptions who would not have to pay (for example, N. Lewis 1983:169). Conquerors subjected conquered peoples, not their own subjects, to taxation. Priests were exempt from the two-drachma tax cited here (Reicke 1974:168; E. Sanders 1990:50); so in later times were rabbis (France 1985:268). Most significant here, dependents of a king were naturally exempt from his taxes (Derrett 1970:255).
Jesus Supplies These Needs As Well As Other Needs (17:27)
The four-drachma coin probably is a Tyrian stater, precisely enough to pay two persons' temple dues (Avi-Yonah 1974-1976:60-61). Following an old Greek story, some Jewish stories of uncertain date speak of God blessing pious people by leading them to find precious objects in fish (Bultmann 1968:238; Jeremias 1971:87). If Peter knew of such stories, the moral of Jesus' causing him to find money in a fish would not be lost on him. This is irony of a sort: the King's children can pay the tax because the King gives them the money to do so (Patte 1987:247). Jesus can take care of his people who walk close to him.