I can do all things through Christ which strengtheneth me.
“Strengtheneth me” is a causative verb meaning to empower, to pour power into one. Paul has such strength so long as Jesus keeps on putting power (dunamis=dynamite) into him. Christ in us, is like spinach to Popeye. The spinach only empowered Popeye over Brutus when he allowed it to be poured into him. By faith and surrender of our will to Christ’s we can indeed do or endure all things through Him.