Sentence:  `` We the people of the Confederate States , each state acting in its sovereign and independent character , in order to form a permanent federal government , establish justice , <WSD>insure</WSD> domestic tranquility , and secure the blessings of liberty to ourselves and our posterity - invoking the favor and the guidance of Almighty God - do ordain and establish this Constitution for the Confederate States of America '' . 
Meaning of the word marked with <WSD> tags:  be careful or certain to do something; make certain of something