Deuteronomy 25:5-9
brothers <0251> [brethren.]
husband's brother .............. brother-in-law <02993 02992> [husband's brother. or, next kinsman.]
first son <01060> [the first-born.]
name ......... name <08034> [that his name.]
[brother's wife. or, next kinsman's wife. go up.]
want ... marry <02654 03947> [I like not.]
sandal <05275 02502> [loose his shoe.]
Pulling off the shoe seems to express his being degraded to the situation of slaves, who generally went barefoot; and spitting in or rather before, (biphney) his face, was a mark of the utmost ignominy.
spit <03417> [spit.]
done <06213> [So shall.]