Whoever denies the Son, the same doesn't have the Father. He who confesses the Son has the Father also.
"Acknowledge" is homologeo and means "to declare openly by way of speaking out freely, such confession being the effect of deep conviction of facts" (Vine 224). Vine, in discussing the word "confess" in Matthew 10:32, says that it "conveys the thought of confessing allegiance to Christ as one’s Master and Lord..." (224). To acknowledge Jesus is more than just a verbal assent. Jesus says, "Not everyone that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven" (Matthew 7:21).