An unbeliever can’t tell if you’re a Christian if you’re still living like the world.

Therefore, you can’t be fruitful.

Mark 4:18-19 (KJV) – and these are they which are sown among thorns; such as hear the word, And the cares of the world, and the deceitfulness of riches, and the lusts of other things entering in, choke the word, and it becometh unfruitful.