Final answer:
The concept of salvation in Christian theology can be framed by predestination or faith alone. Predestination, as taught by Calvin, posits that God has predetermined salvation regardless of human actions, whereas Luther's concept of faith alone suggests that salvation comes through faith, not deeds.
Step-by-step explanation:
The concept of what will ultimately secure a person's salvation has been debated within Christian theology, particularly between notions of predestination and faith or good works. According to Protestant work ethic and the concept of predestination, as presented by figures such as John Calvin, salvation is not something that can be earned or influenced by human actions, because God has already predestined who will be saved and who will not. In contrast, Martin Luther's concept of faith alone suggests that salvation is through faith, not by deeds, aligning with the idea that human beings cannot earn God's grace but are granted it freely through belief.
Each of these perspectives comes with practical implications for believers. The Calvinist view might motivate individuals to live virtuous lives in hope of being among the 'elect,' while Luther's view emphasizes the importance of faith in one's relationship with God. Despite these differing viewpoints, many Christians agree on the importance of leading a life in accordance with one's beliefs, whether as a demonstration of faith or in alignment with God's preordained plan.