Now that the quarterback has recovered from his injury, this week the team will be functioning 'at full strength' again. [=the team will have all its players again]
We are negotiating from a 'position of strength'. [=from a strong position; from a position that gives us an advantage]
He didn't mean to knock you down; he just 'doesn't know his own strength'. [=doesn't realize how strong he really is]
(..) these wagging tongues. This beautiful child... will present me with an heir to the throne. And this marriage... will combine the strength of Wales and Northumbria... and protect our people... from the depredation of the Vikings. That is not enough! (..)1958 The Vikings