There is some belief in the modern Christian era that just because you are saved, it does not mean you have to obey God. Think about it. We preach we are saved by grace through faith (Ephesians 2:8-9) and we are fall short of the glory of God because of our sin (Romans 3:23). We proclaim we can do nothing to save ourselves and Jesus fulfilled the law of God on our behalf. We also teach that nothing in this world can separate us from the love of God (Romans 8:38-39) which means every act of disobedience cannot cut us off from God even after we are saved.
No wonder many Christians think obedience does not matter. So do we still have to obey God after we are saved? The answer is yes. Jesus said, "Whoever has my commandments and keeps them, he it is who loves me. And he who loves me will be loved by my Father, and I will love him and manifest myself to him...If anyone loves me, he will keep my word, and my Father will love him, and we will come to him and make our home with him. Whoever does not love me does not keep my words. And the word that you hear is not mine but the Father's who sent me" (John 14:21, 23-24). The Bible tells us, "By this we know that we love the children of God, when we love God and obey his commandments" (1 John 5:4).
Obeying God means you love Him. Obeying God is our response to His love for us, not to get salvation, but because we have salvation. James 2:14-26 teaches that faith without works is dead. If we are not obeying God, it shows maybe we don't have faith in Christ after all. Jesus said, “Why do you call me ‘Lord, Lord,’ and not do what I tell you?" (Luke 6:46). It makes no sense to call Jesus, "Lord," without any act of obedience coming from His followers. James Montgomery Boice wrote, "Jesus cannot be our Lord without obedience; and if He is not our Lord, we do not belong to Him."
Obeying Christ means we know Him and belong to Him. We testify to God's redemptive work and the regeneration of the Spirit in our lives.