Here "lips" is a metonym for speaking. AT: "by what they say" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# but their heart is far from me
Here "heart" refers to a person's thoughts or emotions. This is a way of saying the people are not truly devoted to God. AT: "but they do not really love me" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-idiom]])