Numbers 8:11-13

KJV_Strongs(i)
  11 H175 And Aaron H5130 shall offer [H8689]   H3881 the Levites H6440 before H3068 the LORD H8573 for an offering H1121 of the children H3478 of Israel H5647 , that they may execute [H8800]   H5656 the service H3068 of the LORD.
  12 H3881 And the Levites H5564 shall lay [H8799]   H3027 their hands H7218 upon the heads H6499 of the bullocks H6213 : and thou shalt offer [H8798]   H259 the one H2403 for a sin offering H259 , and the other H5930 for a burnt offering H3068 , unto the LORD H3722 , to make an atonement [H8763]   H3881 for the Levites.
  13 H5975 And thou shalt set [H8689]   H3881 the Levites H6440 before H175 Aaron H6440 , and before H1121 his sons H5130 , and offer [H8689]   H8573 them for an offering H3068 unto the LORD.