Well, not really.

The part about being thrown into the sea is about the horror that awaits if you sin or lead into sin others, such that it's better to drown oneself than do that.

The part following is about the importance of interpersonal forgiveness, not divine forgiveness.

It's in line with Paul's shtick about not eating meat offered to idols - not because it's wrong - but because if someone else thinks it's wrong and then they do it, you'll have led them into perceived sin.

Taken together, those lines exemplify the most fucked up aspects of canonical Christianity.

• If you do bad things you face horrific divine punishment
• But you must forgive others who do you wrong

This was part of how the church was able to manipulate and abuse their followers for thousands of years.

'Forgiveness' as outlined in that passage has been almost certainly directly cited by the church to silence pedophile victims of its members.

The version of Christianity that passed the survivorship filter of the Roman empire is the one that enabled slavery, servitude, and the oppression of the most vulnerable, and used pleasant sounding terms like 'forgiveness' to do it.