Question

Analysis (What is this saying?)

This point is made, in order that the territories may safely be filled up with slaves, before the formation of State constitutions, and thereby to embarrass the free states[.]

Answer 1

Answer:
This statement is saying that the territories should be filled with slaves before the creation of state laws, in order to make it harder for free states to be established.

Or

This statement is suggesting that the territories should be filled with slaves before the formation of state constitutions in order to make it difficult for the free states. It implies that the goal is to increase the number of slaves in the territories, possibly to put pressure on the free states and to give an advantage to those who support slavery.