I was once in charge of a meeting where I was confronted with this situation. A lady gave forth a powerful and anointed utterance in an unknown tongue. We all waited for the interpretation. Quite soon a man began to give forth what he obviously wanted us to accept as the interpretation. It was, in fact, a series of scripture verses. However, the effect was absolutely deadening and the ‘message’ was out of line with the course in which God had been directing the meeting. I knew that if I pretended to accept this as ‘interpretation’, God’s people would be deceived., and God’s purpose would be hindered. I therefore said: ‘Our brother has just quoted some of the scriptures which he has memorized. Now let us ask God for the true interpretation of what was previously given in an unknown tongue.’ After a few moments of silence, the true interpretation came forth. This time it was in line with the whole course of the meeting, and its effect was to bring new life and liberty, to the whole group of people. I later discovered that the man who gave the first ‘interpretation’ was in some kind of false teaching, and had come to that meeting with the primary intention of propagating that teaching.
Note: This story was told by Derek Prince and shared by Richard Tow in his sermon "Nine Tests of Prophecy."