Heart and Soul
Some of the non-literal translations miss it, but v. 167 actually says "my soul keeps Your testimonies" (NASB). And at the beginning of this Psalm, those who "seek after Him with all their heart" (NASB) will be blessed. God's word is good for behavioral guidance (what to do what not to do) but it's so much more than that. It's not just a set of rules to govern behavior. It's a letter of love to encourage belief - all the way to your soul. Has God's word made an impact deep in your very soul? If not, continue to seek after him with your whole heart. Heart and soul just seem to go together.
