I keep falling into the same sin. I repent, then do it again.

Falling the same way twice makes it feel like something is broken in you specifically. Paul wrote to his own spiritual son about it, and his advice was not to be stronger — it was to leave the room. Joseph got out and left his coat behind. Running was the wise move, not the weak one.

The conversation

The child: “Daddy God, I keep falling into the same sin. I repent, then do it again.”

God: “Nothing's wrong with you that isn't wrong with everyone. Paul told Timothy what to do.”

The child: “What did he say?”

God: “'Flee also youthful lusts: but follow righteousness, faith, charity, peace.'”

God: “Two words change everything: flee and follow. Not fight. Not negotiate.”

The child: “But fleeing feels like weakness.”

God: “Joseph left his garment in her hand and ran. That's not weakness. That's wisdom.”

God: “The strongest thing to do with fire is not touch it.”

The child: “Why 'follow' as well?”

God: “An empty space gets filled. Don't just run from. Run toward.”

The child: “And all the times I've already fallen?”

God: “'If we confess our sins, he is faithful and just to forgive us.' Not some. All.”

The child: “Then I'll stop negotiating. I'll run toward You.”

God: “And I'll be running toward you.”

"Flee also youthful lusts: but follow righteousness, faith, charity, peace, with them that call on the Lord out of a pure heart." 2 Timothy 2:22, KJV