The most familiar, perhaps. The gospel offers total righteousness, i.e. the status of complete innocence and indeed moral perfection, through faith in Jesus Christ. But that faith demands that we abandon any and every other claim to righteousness that we might make. It is Christ or nothing. Hence "I know that nothing good dwells in me, that is, in my flesh". Hence, "I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ and be found in him, not having a righteousness of my own..."
It comes down to: be insecure in yourself, that you might be secure in him.
2. Planning for the future
The text is James 4:13-16, which speaks for itself really:
"Come now, you who say, "Today or tomorrow we will go into such and such a town and spend a year there and trade and make a profit"— yet you do not know what tomorrow will bring. What is your life? For you are a mist that appears for a little time and then vanishes. Instead you ought to say, "If the Lord wills, we will live and do this or that." As it is, you boast in your arrogance. All such boasting is evil."
Only note the depth of insecurity - it is not "if the Lord wills, we will carry out our plans", but "if the Lord wills, we will live..." But within that insecurity, there is great security. The Lord's will is certain, and if we know him at all then we know that his will is good.
Just a thought: when I have done everything necessary from a human standpoint to prepare to address people on God's behalf(!), it is still utterly impossible that I should do what I plan to do. I cannot speak God's word. As I mount the pulpit, I am utterly insecure. But God has promised to speak, and so in realising my inability and insecurity I am both able and secure.
(As an aside, you should read Glen's article on preaching at Theology Network - I read it, and behold it was very good).
All in all, I am radically undercut by the gospel. If I am to be justified in any of my endeavours, it must be in God through Christ.