I can't get out of my mind the story of Balaam in Numbers 22-25. The short version is that Balak, king of the Moabites knew Israel was coming his way, and was afraid. So he hired a fortune-teller to curse them, believing that if they were cursed, he and his people would be saved. Balaam had dollar signs in his eyes (OK, maybe they were shekel signs, but you get the picture) and agreed to the deal, but when the time came for him to come across for his benefactor, all he could do was bless Israel. Turns out that God intervened in spite of him. Three times he tried to curse Israel; three times he blessed them instead.
Understandably frustrated and angry that Balaam had double-crossed him, Balak sent him packing. But before he left, Balaam gave the king a bit of effective advice. Essentially, he told him that if he sent in a few women to entice the men into sexual sin, God couldn't just sit idly by, but would have to judge them. They would in essence, bring the curse upon themselves.
There's much food for thought here, but what strikes me is the contrast between an external and an internal curse. The story tells us that no curse spoken against God's people can stand because God stands between those who do the cursing and those being cursed. But we can bring trouble on ourselves by willingly choosing actions and attitudes that are self-destructive. In other words, it's not what happens to us that is as damaging as what happens in us. It's when I start believing those curses, when I start believing the devil's lies that trouble comes. Satan himself can curse me all day without effect unless I begin believing him.
Whenever we say, "I'm not good enough, strong enough, smart enough," we are opening the door to self induced curses, for which there is no remedy save the grace of God in the Cross of Christ. Jesus became a curse for us, taking all mankind's curses on himself. They were nailed to the cross (Colossians 2:14). The fact of the matter is, I am not good enough, strong enough, or smart enough. But Jesus is, and if he is living within me, his ability more than trumps my inability. My biggest problem in life is myself. Often like St. Paul, I have cried out, "Who shall deliver me from this body of death?" and the answer always comes back, "Thanks be to God through Jesus Christ our Lord." It's not a matter of how hard I try, but where I look. Eyes on Christ makes all the difference.