Seems like a fairly simple set of requirements for salvation.
Consider:
1 John 2: 3 And hereby we do know that we know him, if we keep his commandments.
4 He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.
5 But whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in him.
6 He that saith he abideth in him ought himself also so to walk, even as he walked.
A mere profession of faith is not enough. We must keep His commandments and walk in Him.
SD
"A mere profession of faith is not enough. We must keep His commandments and walk in Him."
I'm sure I don't need to remind you that a "mere profession of faith" in those days, specifically the public confession "Jesus is Lord" could have gotten you beaten up killed.
Similarly, the phrase "believe in your heart" speaks of a lack of hypocracy of they type exibited by the "Lord, Lord!" crowd. Faith, true faith from the heart is the primary "work" of God. All other works flow from that. A faith which doesn't exhibit obediance is not a true faith from the heart, but rather a faith of the head or worse, of just the mouth.
How many commands did the theif on the cross have time to keep?