"Strongest weakness" means prayer is perhaps the strongest weapon in the soldier of Christ's arsenal, but a lot of believers in prayer are weak in their use of the blessing.
The point we noticed from the Scriptures Sunday is that God wants us to pray about everything and everyone. He wants us to draw close to him through prayer to ask about small things, but also the very big things. Our prayers affect not only this world, but eternity!
Ephesians 3:20-21 says, "Now to him who is able to do far more abundantly than all that we ask or think, according to the power at work within us, to him be glory in the church and in Christ Jesus throughout all generations, forever and ever, amen" (ESV). This passage has to do with more than just prayer, but it includes prayer. "All that we ask or think." Think about that.
There's nothing too big for God's children to ask him in prayer. We can't even think big enough to be too big for God. So pray strong!