Commentaries:
This was written to the Ephesian era of the church (Revelation 2:1-7), which lost its first love. But when the people were in the bloom of their first love, were they enthusiastic! They put everything into the relationship. They yielded themselves to God. They were obedient and submissive. They were in no way neglecting the relationship.
Yet, even though these people made such a great start, it was possible for their relationship with God to deteriorate. The evidence is in Revelation 2 and in the book of Hebrews. They allowed the relationship to degenerate through neglect.
John W. Ritenbaugh
Conviction and Moses