I write to you, young men, because you are strong, and the word of God abides in you, and you have overcome the evil one. 1 John 2:14
How are these young men strong?
The abiding sense of their own weakness keeps them dependant upon him, so that the more they feel of their helplessness, the stronger they grow: because they live more upon Christ for strength, which illustrates that seeming paradox of the apostles, “When I am weak, then am I strong”—when I am most sensible of my own weakness, then am I strongest in the Lord, his strength is then perfected in me. And his strength is put forth in the effectual working of it by believing. It is not, neither can it be inherent in them, who without Christ can do nothing, but it is brought in by faith; nor does faith bring it in to lodge it, or lay it up in store, till it shall be wanted, but when it is wanted, faith then regards the promise, looks up to Christ to fulfil it, and receives strength out of his fulness. And being his, freely promised, and freely given, it is therefore called the strength of grace, “Thou therefore “my son, says Paul to Timothy, be strong “in the grace that is in Christ Jesus.” Strong faith gets strong grace from Christ, according as it is written—” All things “are possible to him that believeth :” for according to his faith it shall be done unto him. If his faith reach to the full extent of the promises he shall find all things possible, which God hath promised, yea he shall be able to do all things, through Christ strengthening him.
Romaine, William. “Treatise upon the life of faith.”