Lies are a form of betrayal against God. This is why the 9th commandment includes all forms of lies, and not just false testimonies against one’s neighbour. One can violate the 9th commandment without necessarily speaking untrue words of his or her neighbor.
Many biblical passages speak of how God is opposed to all forms of lies, weather they involve other individuals or not. In Proverbs 6:16-19 it is written:
“There are six things that the Lord hates, seven that are an abomination to him: haughty eyes, a lying tongue, and hands that shed innocent blood, a heart that devises wicked plans, feet that make haste to run to evil, a false witness who breathes out lies, and one who sows discord among brothers.”
The passage above speaks about how the Lord hates lies in all its forms. Unfortunately, not very many people understand this. There are some people who read the bible in an overly simplistic way, and assume that the only kinds of lies that are considered to be moral sins are those that give false testimony against another person.