Scripture tells us to do and not to do many things. In my estimation, when Scripture tells us not to commit adultery we must not commit adultery and equally when Scripture tells us to make disciples of all the nations (evangelism) we must do this as well. As far as I am concerned not evangelizing is just as bad as sleeping with a neighbor’s wife, both are disobedience, both are sin.
Is not being a Christian (truly regenerated) more than what we do not do, but equally what we do for the glory of God?
The truth can be found in Matthew 7:21, John 14:15, James 2:17, and many more. We must do God's Will; anything we are commanded to do within Scripture is in God's Will. What is easily gathered from those three references is that the truly regenerated man will produce works; it will be his desire and life goal to glorify God. I believe that it goes without saying that even the elect go through times of compromise and complacency but that does not define God's new creations.
Let us thoroughly look at passage Matthew 10:27-28 and to do this we will look at the chapter as a whole. Our main text (verses 27-28) is,
(27) "What I tell you in the darkness, speak in the light; and what you hear whispered in your ear, proclaim upon the housetops.
(28) "Do not fear those who kill the body but are unable to kill the soul; but rather fear Him who is able to destroy both soul and body in hell.
Let’s first seek out the context, in verse 1 through 5 we see Jesus is instructing the Apostles prior sending them out to proclaim (verse 6), “The Kingdom of Heaven is at Hand.” A reoccurring idea that the disciples will be hated for preaching Christ’s message is seen both before and after our target passage. Here is my overview of Matthew 7:27-28 containing pertinent context: Jesus, before sending the Apostles out to preach the coming Kingdom of Heaven gives them instructions in Matthew Chapter 10. He repeatedly informs the Apostles that they will be hated for Christ’s message which they are to proclaim; Jesus is guiding the Apostle’s into God’s Will and certainly expects them to be obedient. His expectations of obedience to God’s Will is evident in verse 28, the point is to not allow fear of men to subvert our obedience in preaching the Gospel, that the punishment for disobedience towards God far outweighs mans persecution for obedience towards God.
Should we have fear that God will cast us into Hell for disobedience? Let’s define disobedience for our intended context, to disobey God’s Will, which is to do what is contrary to what God would have us do. There are many things that Scripture tells us to do and many Scriptures that list things that we are to abstain from, to oppose Scripture is disobedience. Within the two Commandments Jesus emphasized, Deuteronomy 6:5, "You shall love the LORD your God with all your heart and with all your soul and with all your might.” And Leviticus 19:18, “you shall not take vengeance, nor bear any grudge against the sons of your people, but you shall love your neighbor as yourself; I am the LORD.”