Do EP advocates disapprove of religious poetry (hymns, in this case) for personal edification? Because that's the sense of some of the comments I'm getting, but I'm not quite aware of how distinctions are drawn--or if there are any--between public/private worship, poetry and song, etc.
There is a variance of opinion on what to do with hymns of mere human composure. Some believe that the principle that we should only worship God as He commands applies to public worship only, so there is no problem in private or family. Some will hold that the principle additionally applies to family worship, so there is no problem with private. Some hold that the principle holds in all settings and will say hymns of themselves violate the principle and therefore avoid them. Some who hold that the principle holds in all settings will recognize a place for hymns in the category of "meditation" or "recreation" (i.e., a part of one's generic worship of doing all things to the glory of God), although some people in this category will avoid hymns anyway for other reasons (e.g., They are used as false worship in many churches, so why would we want to have anything to do with them? Or, the use of hymns in any setting tends to eventually make its way into worship, so let's avoid them. Or, some or all hymns that currently exist are inherently an attempt to worship God--despite their theoretical validity--so let's avoid those ones.).
Undoutebdly though, even if they find some place for hymns of mere human composure, the EPer will find the psalms to be their favorite Book of Praise (Hymn Book) even for meditation or recreation: for it is the Word of God upon which they are meditating day and night. Hence, some of the comments on this thread (others are viewing "hymn" in the title of the thread to refer to songs that are not the psalms and are responding accordingly).
Here is my opinion written on a Facebook comment in response to this question so far as how hymns relate to the Second Commanement.
"I agree with your position that hymns ought not to be sung as a specific act of worship to God, even in private; and that the rule for worshipping God is the same in public and in private. However, the way I see it, outside of that setting, I would characterize hymn singing as "meditation" or "religious recreation" (John Brown of Haddington's phrase from his preface to the 1650 Psalter).
The way I see it: Leviticus 10 shows us that the worship that is regulated by God's will is an action that involves "drawing nigh unto God" for the purposes of "worshipping" him (meaning, a "bowing down;" hence, involving a full and complete attention and submission to God's will). An action joined with this movement and with this intent is an attempt to worship by a specific act and must strictly be regulated by God's will. One could make a painting. If however one attempts to draw near to God to worship God either by making the painting or with the painting itself, they are acting against God's law.
As for meditation, it is more inward focused, contemplative; a communing with one's heart; a turning over of one's thoughts; done especially with the intent of stirring one's heart up to worship God (perhaps by prayer or by singing a psalm or portion of a psalm). Meditation is to be performed on all sorts of subjects: God's nature, will, works of providence and works of creation, God's word. Meditation can take the form of a song, as seen, e.g., by Psalm 119. We can thereby also see that although meditation can be found (and ought to be found) in a specific act of worship of God (namely, singing the psalms), a meditation itself is not necessarily a specific act of worship, as it is not necessarily a drawing near to God to worship him.
Some hymns are more meditative in nature rather than an inherent attempt to draw near to God to worship him. Indeed, if one is singing such a hymn while busy with something else, it cannot be viewed as worship: one is distracted by other things and cannot draw near to God with the purposes of worshipping him. Whatever else one might say, if one can find a hymn that is a mere meditation instead of an inherent attempt to worship God in a specific manner, singing or composing that hymn is lawful in that respect. (There may be other reasons to avoid singing hymns though or that might make singing them unlawful; I personally do not sing them.) Intent is also key here as to whether the hymn is being used meditatively or being used as an attempt to worship God by a specific action."