Parashas Vayikra · Aliyah 1 · Passuk 9
Chabad.org — English translation + Rashi
Torah Temima points to Toras Kohanim on the washing of the innards and legs.
E-Daf / Tsurras Hadaf (size=3 where available)
PDF of the daf / source
English: “And its innards and its legs he shall wash with water” – so that they are clean.
Requirement that the inner parts and the legs be washed before they are offered — they must be clean when placed on the altar.
Even the parts that are not outwardly visible are washed and prepared with care, teaching that the entire offering — inward and outward — is brought in a state of purity and dignity before Hashem.