We like to say, nothing happens by chance.  But clearly in this Book of Ruth we can see a theology of chance threaded throughout the writing.  By chance Ruth comes to the field of Boaz (2:3). There she receives the blessing of grain through the faithfulness of Boaz. By chance Boaz lies down at the end of the heap of grain (3:7). By chance Mr. So-and-So appears at the city gate (4:1) so that Boaz can faithfully settle the issue of redemption to effect blessing upon the widows. Within human luck, then lies divine intentionality.  A faithful God blesses through a faithful people. (David N. Freedman, 1922, The Anchor Bible Dictionary, V. 5)