Unworthy - Horse Pucky!

In the NASV(1995) version, the word "unworthy" only appears 4 times in the entire Bible. Genesis 32:10, Luke 17:10, Acts 13:46, 1 Corinthians 11:27. In Genesis 32:10, Israel uses the word to describe himself to God while in the process of reminding God of His own promise. This is actually an example of Luke 17:10 in action. 

So you too, when you do all the things which are commanded you, say, ‘We are unworthy slaves; we have done only that which we ought to have done.’Luke 17:10.

However in John 15:15, Jesus redefines His disciples as "NO LONGER SLAVES." Why? because slaves do not know their master's business. When the disciples received the Holy Spirit, they became apostles because they both knew the Father's will and had the power to do the Father's will including but not limited to signs and wonders. The disciples know the Father's business because Jesus revealed it to them and because the disciples received it by faith. Thus, we are not to approach the throne of grace as slaves but in confidence as children of the Father, John 16:26. "Children of the Father" is defined in John 16:27. 

How often do little children tell their parents "Dad, you said..." in order to get what they want from their father? Though Israel called himself an unworthy slave in Genesis 32:10, Israel was actually behaving like a little child who reminds his father of what his father said. Thus, Israel's actions became a type or sign of the process God uses to call mysteries out of the darkness and into His light. That is why it is written, "I said, 'You are gods, And all of you are sons of the Most High."

Furthermore in Acts 13:46, Paul rebukes the Jews for condemning themselves as unworthy for eternal life i.e. sons of the Most High. The Jews were literally condemning themselves by contradicting God's words. Jesus defines a right judgment in John 8:16 as a judgment that agrees with the Father's words. So since God has esteemed us worthy of eternal life by His grace and mercy, then Paul is correct to rebuke the Jews for judging themselves in a wrong manner or contrary to God's words. Judging ourselves contrary to the Father's judgment is false humility.

There is a big difference between humans humbly calling themselves God's slave, and God saying "No longer do I call you slaves." Remember, Jesus was made a little lower than the angels for the time He walked on the earth. 

Have this attitude in yourselves which was also in Christ Jesus, who, although He existed in the form of God, did not regard equality with God a thing to be grasped, but emptied Himself, taking the form of a bond-servant, and being made in the likeness of men. Philippians 2:5–7.

Finally, we are told in 1 Corinthians 11:27 that if we eat the bread or drink the cup of the Lord in an unworthy manner we are guilty of the body and blood of the Lord. Paul further defines "unworthy manner" in 1 Corinthians 11:29-30 which reads:

For he who eats and drinks, eats and drinks judgment to himself if he does not judge the body rightly. For this reason many among you are weak and sick, and a number asleep. 1 Co 11:29–30.

This literally means that if we judge each other incorrectly and take communion we eat condemnation upon ourselves and become sick and die.

When humans preach that man is unworthy of God, those preachers contradict Colossians 1:9 which commands us to walk in a manner worthy of God thereby proclaiming it to be possible to be worthy of God. This is, of course, provided we are doers of the word and not hearers only. Man is worthy of God. However, God is both in heaven and in hell as King David said. Thus, we will either be worthy of God's presence (wrath) in hell or we will be worthy of God's presence in heaven.