Explanation

The Prophet (may Allah's peace and blessings be upon him) says, "Allah has appointed an angel in charge of the womb", i.e. Allah, the Almighty, has assigned an angel to be in charge of the womb, which is the place where a child is created inside his mother. "And the angel says: 'O Lord, (it is) a sperm drop!", i.e. O Lord, this is a sperm drop, which is the man's semen. The same applies to the next statement: "O Lord, (it is now ) a clot!", i.e. O Lord, this is a clot; which is thick blood stuck together. Then he says, "O Lord, (it is now) a piece of flesh", i.e. O Lord, this is a piece of flesh. It was explained in another narration that each of these development stages in the womb takes forty days. Then the Prophet (may Allah's peace and blessings be upon him) said: "Then, when Allah wills to complete its creation", i.e. the small piece of flesh because it is the last stage of development, and completing its creation is by blowing the soul into it after 120 days, as mentioned in another narration. Then the angel says: "O Lord, (will it be) a male or female?", i.e. so I can write it down. "Wretched or blessed?", i.e. is it a wretched one from the inhabitants of Hellfire, then I will write it down, or a happy one from the inhabitants of Paradise then I will write it down. "How much will his provisions be?", i.e. will it be little or abundant? "How long will he live?", i.e. will he have a long or short life? "All that is written while the fetus is still in his mother's womb", i.e. the angel will write down everything mentioned just as Allah orders him, while the fetus is still in its mother's womb.