Jesus says if we hold to His teaching, we are truly His disciples; then we will know the truth and the truth will set us free (John 8:31–32). The truth of the gospel sets us free from the slavery of self-service, as it calls us to live our lives for the purpose of redemption.
The call of humanity is self-preservation, but the call of Christianity is self-sacrifice for the sake of redemption.
When we choose to serve self, we are choosing a purpose that cannot be fulfilling.
Choosing to serve self is choosing to save our lives. Living for self, we are living to protect ourselves from sacrifice on behalf of others. This lifestyle leaves us disappointed and frustrated with a continual lust for more.
So I tell you this, and insist on it in the Lord, that you must no longer live as the Gentiles do, in the futility of their thinking. 18 They are darkened in their understanding and separated from the life of God because of the ignorance that is in them due to the hardening of their hearts. 19 Having lost all sensitivity, they have given themselves over to sensuality so as to indulge in every kind of impurity, with a continual lust for more.
20 You, however, did not come to know Christ that way. 21 Surely you heard of him and were taught in him in accordance with the truth that is in Jesus. 22 You were taught, with regard to your former way of life, to put off your old self, which is being corrupted by its deceitful desires; 23 to be made new in the attitude of your minds; 24 and to put on the new self, created to be like God in true righteousness and holiness. (Eph 4:17–24 NIV)
Then he called the crowd to him along with his disciples and said: “If anyone would come after me, he must deny himself and take up his cross and follow me. 35 For whoever wants to save his life will lose it, but whoever loses his life for me and for the gospel will save it. 36 What good is it for a man to gain the whole world, yet forfeit his soul? 37 Or what can a man give in exchange for his soul? 38 If anyone is ashamed of me and my words in this adulterous and sinful generation, the Son of Man will be ashamed of him when he comes in his Father’s glory with the holy angels.” (Mark 8:34–38)