Laodicea is described as being materialistic, self-satisfied, no longer interested in doing God's work whether it is in their personal lives or as a public proclamation. Jesus Christ's rebuke here is the strongest in the Bible! When He says He will vomit them out of His mouth, it shows great distaste - His own people are not enthusiastic or zealous about doing a work!
Their estimation of themselves strongly implies spiritual self-satisfaction. They evaluate themselves on the basis of their material wealth, but when God looks, He judges them on the basis of their spirituality and find they lack a great deal. Being worth nothing, they had to be spit out.
Their spiritual condition is so bad that the Savior is on the outside looking in! He has to knock on the door, as it were, to be let into services or into their lives. It is no wonder that He says that He will vomit them out! So He says, "If any man hear my voice. . . ." If anyone is willing to repent, He will come in. He is appealing to anyone in that condition to change his or her attitude.
John W. Ritenbaugh
Revelation 10 and the Laodicean Church