For God has not given us a spirit of fear, but of power and of love and of a sound mind. (2 Timothy 1:7) Read the whole chapter here.
God gives us a spirit of faith. God doesn't give a spirit of fear.
When you place your trust in Jesus, the Holy Spirit comes to live within you. He gives you power (Acts 1:8).
When you place your trust in Jesus, the Holy Spirit begins to make us more and more like Jesus. We become more loving.
When you place your trust in Jesus, the Holy Spirit begins to convict you of sin, leading you into repentance. Each time you are tempted, you have a choice. You can choose to be disciplined and follow Jesus more closely, or you can choose to give into the sin. The Holy Spirit gives each of us the power and ability to choose discipline over sin.
Walking in the spirit of faith that God has given us looks like trusting in Jesus, and walking in the power, love, and discipline that he alone can give.