Legal documents are usually created in response to some event. Often that event is not stated in the document–try and determine what it is.
Legal documents use words that may be used on “common conversation” with a slightly different meaning. Make certain you are interpreting words in the legal sense not in the everyday language sense.
Legal documents are created in the context of contemporary law and contemporary legal practice. Try and determine what those are. What sufficed in 1719 might not be what suffices in 2019.