Since there is no condemnation for all that are in Christ Jesus, does the believer’s lifestyle really matter, for he is under grace? (Romans 8)

Scripture reveals that Christ followers, Christians dedicated their lives to Christ and not to consumerism, materialism, humanism or any other ism (ideology or philosophy). In fact they referred to Him as Lord, meaning complete master, the authority in which they submitted and laid down their lives.
The Apostle Paul in the sixth chapter of Romans writes, “But now that you have been set free from sin and have become slaves of God, the fruit you get leads to sanctification and its end, eternal life” (v. 22). Jesus did not simply pay the price for sinners, setting them free to go their own way again, rather He sets them free from the bonds of sin for His purpose giving them identity. A slave as referred to here by the Apostle was known to receive his identity from his master in the ancient world and likewise a Father would give identity to his off spring too as referred to in Romans 8, “you have received the Spirit of adoption as sons, by whom we cry, “Abba! Father!” (Roman 8:15)… The Apostle later adds how one should think of this new identity in every day life, “brothers and sisters, in view of God’s mercy, [you are] to offer your bodies as a living sacrifice, holy and pleasing to God—this is your true and proper worship. Do not conform to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God’s will is—his good, pleasing and perfect will…” (Romans 12:1-2)
This surrender and allegiance to Christ alone as a slave was never thought to be optional. Jesus told His followers in the Upper Room, “You are my friends if you do what I command you” and prior to this command He told a crowd, “If you abide in my word, you are truly my disciples, and you will know the truth, and the truth will set you free” (John 15:14, 8:31,32)(ESV). Jesus also directly says, “If anyone serves me, he must follow me; and where I am, there will my servant be also. If anyone serves me, the Father will honor him” and “If anyone would come after me, let him deny himself and take up his cross daily and follow me” (John 12:26; Luke 9:23)(ESV).
“If” is written in all four verse “if you” or “if anyone” … “If” here is used as a conditional clause. A conditional statement discusses known factors or hypothetical situations and their consequences (“Grammarly,” 2017, Para. 2). In logic there is a similar statement, symbolized by p è q, also known as an if-then statement in which p is a hypothesis (premise) and q is a conclusion.
From Jesus’s statements these principles can be derived,
1) If one is a true believer, he will abide in God’s Word, (Evidence-Fruit)
2) If one is truly born of the Spirit, he will preserver holding to the teachings of Jesus,
3) If one is a true Christian, he will be obedient to Christ (the test is true obedience)
4) If one is to be obedient to Christ, he must deny self and surrender all (Rom 12:1)
When one proclaimed to be a Christian in the ancient world it was automatically assumed that his or her self-identity was found in his Master, Lord, Deliverer, Purchaser, Christ, for He was their complete master (Lord) who purchased them.
Early Christians were urged to count the cost of following Christ (Luke 14:28). There were great crowds that followed Jesus and He knew there were some only there for the benefits (food, healing, entertainment). By counting the cost Jesus was saying, recognize the terms and conditions before following me because it will cost you all including your identify. In other words you could not simply add Christ to your current life and life style. You could not follow Christ and the world (Matthew 6:24). Christ was to be the center of the believer’s life and was for they risked everything, denying their very lives (imprisonment and/or death)(Phil. 1:21). Therefore the proclamation of being a Christian was not simply a profession as so often observed today, rather it was an identity change received after true profession.