By the virtue of man's Adamic nature, man is born to be wicked. A new nature is imputed in man through the new nature of Christ.
John 1:12 KJV
But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name
Romans 3:23 KJV
For all have sinned, and come short of the glory of God;
Romans 6:23 KJV
For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
The truth is that, no religion can give a new life. One needs to be born again in other to enjoy this new life promised
John 3:3 KJV
Jesus answered and said unto him, Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God.
To have access to God and to be able to live a Godly life, you have to surrender your life to God through genuine repentance and faith in Christ.
Now, let us look at the meaning of this words;
Develop:
To develop means to change and grow, to change and become larger, to be stronger or to be more impressive, to be successful or to advance or to change something or someone
Character:
Character in this context means positive qualities. These are distinctive qualities that makes someone or something interesting or attractive, especially somebody's qualities of mind and feeling.
Christian/Godly character:
Character use to be the product of struggle and energy of the flesh under the law of relationship between people and God. This is what is believed by people through false teaching. It is preached that individual habits are determined by the totality of his/her acts, character is determined by the totality of individual's habits and destiny is determined by character.
The truth is once you are born again, you are a new creature and whatever might have been true under law doesn't count again and the doctrine is foreign to grace. Destiny is no more determined by self-promoted character, it now depends only on faith.
Therefore, the way to a victorious life is to walk in spirit. Your responsibility as a believer is not to walk but to yield to the Spirit who promotes the walk. When you yield, you get an instant and perfect result.
So long as you continue to walk in the power of the spirit, the spiritual life will be experienced. However, if the adjustment to the spirit cease, the walk will also cease, and the flesh will be manifested again.