Ulangan 21:4

21:4 and bring the heifer down to a wadi with flowing water, ¹  to a valley that is neither plowed nor sown. ²  There at the wadi they are to break the heifer’s neck.

Ulangan 25:9

25:9 then his sister-in-law must approach him in view of the elders, remove his sandal from his foot, and spit in his face. ³  She will then respond, “Thus may it be done to any man who does not maintain his brother’s family line!” ⁴ 

[21:4]  ¹ tn The combination “a wadi with flowing water” is necessary because a wadi (נַחַל, nakhal) was ordinarily a dry stream or riverbed. For this ritual, however, a perennial stream must be chosen so that there would be fresh, rushing water.

[21:4]  ² sn The unworked heifer, fresh stream, and uncultivated valley speak of ritual purity – of freedom from human contamination.

[25:9]  ³ sn The removal of the sandal was likely symbolic of the relinquishment by the man of any claim to his dead brother’s estate since the sandal was associated with the soil or land (cf. Ruth 4:7-8). Spitting in the face was a sign of utmost disgust or disdain, an emotion the rejected widow would feel toward her uncooperative brother-in-law (cf. Num 12:14; Lev 15:8). See W. Bailey, NIDOTTE 2:544.

[25:9]  ⁴ tn Heb “build the house of his brother”; TEV “refuses to give his brother a descendant”; NLT “refuses to raise up a son for his brother.”