"Examine" (dokimazo) means to prove, to test, to determine if metal is pure. It connotes approval rather than condemnation. Our self-evaluation is an honest inspection to see if we are progressing as God expects us to. He wants us to see what the attitude of our heart is! Then we can take the Passover confidently with a right heart.
When Paul says "examine yourself," he is not referring to an "out-of-body experience," yet it could be likened to that. God wants us to stand to one side and look at ourselves, making an honest evaluation of our progress over the past year.
Some of us do not truly realize what a wonderful season the pre-Passover period is. We can fool ourselves all year long by rarely studying, praying sporadically, and maintaining our vices, but if we remotely care what God thinks of us, we are forced to face our true natures in this self-examination. God wants us to do this for our own good. He wants us to see what we need to work on and change.
He wants us to worship Him in Spirit and truth (John 4:24). He wants us to be honest in our evaluation. Though we often dredge up past problems and old feelings from childhood of which we have long ago repented, God wants us to examine our present state. We must look for flaws we have now and seriously and positively make the necessary changes in our lives.