For example, farther and further are mostly interchangeable, but they are subtly different. For example, farther should be used with measures of distance, whereas further is for measures of degree or time; further is also used as the comparative form of far. Although Wiktionary tells me that experts have never made a fuss about this distinction, I tend to err on the side of grammar nerditry.

Songs are different than regular usage, though. Grammatical constraints are often relaxed or broken for artistic effect or because of the exigency of other types of constraints. It used to irk me when artists would use the improper form of lay or lie in their songs, until I thought of how weird it would sound to use the correct form. At the same time, I have the utmost respect for artists who navigate treacherous grammatical straits properly and elegantly.

Quick grammar lesson: to lay is transitive, as in “I lay the book down on the table.” To lie is intransitive, as in “I lie down on the couch to take a nap.” The confusion arises because the past tense of lie is lay. I lie / I lay / I had lain. I lay / I laid / I had laid. I’ll try not to judge you for getting this wrong.

A recent example is The Bird & The Bee’s Love Letter to Japan: “and now, all my heart I will lay down precisely at your feet”. The present tense of to lay. The transitive one. Perfect.