http://www.halakhah.com/sanhedrin/sanhedrin_54.html "Rab said: **Pederasty with a child below nine years of age is not deemed as pederasty** with a child above that. Samuel said: Pederasty with a child below three years is not treated as with a child above that." (footnotes) "I.e., Rab makes nine years the minimum; but if one committed sodomy with a child of lesser age, no guilt is incurred. Samuel makes three the minimum. At nine years a male attains sexual matureness. Lev. XVIII, 22. Thus the point of comparison is the **sexual matureness of woman, which is reached at the age of three**."