[Old Yeller]

"The truth is that nobody can be sure of their salvation until it happens. "

John 5:24
Most assuredly, I say to you, he who hears My word and believes in Him who sent Me has everlasting life, and shall not come into judgment, but has passed from death into life.

[vladimir998]

John 15:10

“If you keep my commands, you will remain in my love, just as I have kept my Father’s commands and remain in his love.”

So, if you don’t keep Jesus’ commands you will not remain in His love. Clearly more than just faith is needed. You must actually keep Jesus’ commands.