Many Christian songs are uplifting and they sometimes mention or hint at God's promises. In general, that is nice, but it can be misleading for those who are not intimate with the full background of said promises.

Some promises are conditional. But the conditions are not mentioned in the song. Some promises are made for very specific people in very specific circumstance. But the song abbreviates and generalises the story.

Complications can arise when people sing the songs and take the words as gospels without deep understanding of the full background. It is like picking and choosing Bible verses out of context.

Obviously there is only so much song writers can fit into the lyrics. The onus is on us to read and understand the Bible properly and enjoy the songs within the proper Biblical contexts. The songs are just reminders and abbreviated artistic expressions.