The verb abridge means to reduce or shorten a written work without sacrificing the text’s sense.  

Synonyms are shorten, truncate, curtail,  or trim.

The word origins from Middle English (1300) abriggen meaning “to reduce, diminish, shorten” and from the Old French (12c.) abrigier. It also origins from Late Latin abbreviare meaning “make short” from ad meaning “to” plus breviare meaning “shorten”.

It is not my intention to abridge contexts.

There are principles or some contexts that might have been abridged in this book. 

My mother carefully abridged her written speech since she didn’t want to talk much on tomorrow’s conference.