Imamat 27:32

27:32 All the tithe of herd or flock, everything which passes under the rod, the tenth one will be holy to the Lord. ¹ 

[27:32]  ¹ sn The tithed animal was the tenth one that passed under the shepherd’s rod or staff as they were being counted (see J. E. Hartley, Leviticus [WBC], 485, and B. A. Levine, Leviticus [JPSTC], 200).