Jesus Paid it All
Jesus said it is finished. Everything is done. I don’t need to add anything.
If somebody tells you that you need to add something to your salvation, just the idea of us sinful humans adding to our salvation is anti-gospel. It is the opposite of the gospel. If there is one thing we have added to God’s saving work -it is our sin.
Don’t treat Jesus like a downpayment and now you are paying the installment. He paid it all.