Plato attributes the famous saying, “Know thyself” (Γνώθι σεατόν) to fellow Greek philosopher and mentor, Socrates. Socrates’ notion seems to be the preoccupation of the privileged, an activity of leisure. Not so. Consider what Paul had to say to the church at Corinth when preparing to visit them:
“Examine yourselves; to see whether you are in the faith. Test yourselves. Or do you not realize this about yourselves, that Jesus Christ is in you?” (2 Corinthians 13:5, ESV)
While Plato was using Socrates’ teaching to make some philosophical point to other philosophers, Paul was writing to ordinary people, some of them really messed up and in need of transformation, in order to give them means to remain strong in the faith, to make a daily choice to stand.
To examine and test one’s soul is no easy task. Says commentator Simon J. Kistemaker: “True faith is active and constantly forces Christians to test themselves to see whether Jesus Christ through the Holy spirit lives in their hearts. True faith testifies to intimate fellowship with the Father and the Son (I John 1:3).” (Emphasis mine.)
Yet this intimate fellowship we have with the Father and the Son draws us into deeper, more challenging testing. This fellowship takes us beyond our own conscience, placing us in the domain of the Father’s testing us. Consider what is written in Deuteronomy 8:2-3: “And you shall remember the whole way that the Lord your God has led you these forty years in the wilderness, that he might humble you, testing you to know what was in your heart, whether you would keep his commandments or not. And he humbled you and let you hunger and fed you with manna, which you did not know, nor did your fathers know, that he might make you know that man does not live by bread alone, but man lives by every word that comes from the mouth of the Lord.”
When we examine or test ourselves, we find either affirmation that we are in Christ or not. When God the Father tests us, he humbles us, removes our mistaken ideas that we exist on the merit of our own strength and genius, to see whether or not we will still follow him when it doesn’t make us look good in the eyes of those around us. What pride can we possibly derive from being fed and watered and lead, helpless and needy?
We are prone toward pride and independence, are we not? Hence the warning in verses 17-18: “Beware lest you say in your heart, ‘My power and the might of my hand have gotten me this wealth.’ You shall remember the Lord your God, for it is he who gives you power to get wealth, that he may confirm his covenant that he swore to your fathers, as it is this day.”
It can be easy to become discouraged in times of testing, misinterpreting the purpose of the test. We can feel attacked, forgotten, isolated, devalued. We can fall into the Satanic trap of feeling less than zero. But, in this case, truth trumps emotion.
Deuteronomy 8:16 indicates that God humbles us to do us good. He can use broken, submitted, humble servants: those are qualities ascribed to Jesus’ time in the flesh, on the earth. Our pilgrimage is to become Christ-like is it not?
Should you choose to take up the mission to shake the gates of Hell in your generation, you must take up the habit of examining and testing yourself, to see whether or not you are in the faith. You must take up the habit of submitting to the Father, Son, and Holy Spirit that Jesus might be represented well in this generation, that those who have ears to hear might receive the gospel, that those who choose to reject Him will do so not on the basis of ignorance, but having been informed of what they choose to reject. Friend, “Know thy faith.”
 Kistemaker, Simon J. New Testament Commentary: 2 Corinthians. Pg. 450. Grand Rapids: Baker Academic, 1997.