#Now Rachel ... upon them

The word "now" is used here to mark a change from the story to background information about Rachel. (See: [[:en:ta:vol2:translate:writing_background]])

#saddle

a seat placed on the back of an animal so a person can ride on it

#my master

Calling someone "my master" is a way of honoring them.

#that I cannot stand up before you

"because I am unable to stand up in your presence"

#for I am having my period

This refers to the time of the month when a woman bleeds from her womb. (See: [[:en:ta:vol2:translate:figs_euphemism]])