Salvation: Know the Lord

INTRODUCTION: Until now, I have never been able to find a sufficient answer for how an individual was saved in the Old Testament. I was taught that salvation in every dispensation, except the Church Age, involved a man earning it through some element of his works. Yet, I came to realize that no man will ever have opportunity to boast for his salvation when standing before God after death. My question remained: does the Bible clearly teach what differentiated between a lost and saved man in the Old Testament?