'Walking' in the Bible

If we say we have fellowship with him and yet keep on walking in the darkness, we are lying and not practicing the truth.

but if we [really] walk in the Light [that is, live each and every day in conformity with the precepts of God], as He Himself is in the Light, we have [true, unbroken] fellowship with one another [He with us, and we with Him], and the blood of Jesus His Son cleanses us from all sin [by erasing the stain of sin, keeping us cleansed from sin in all its forms and manifestations].

But the one who habitually hates (works against) his brother [in Christ] is in [spiritual] darkness and is walking in the darkness, and does not know where he is going because the darkness has blinded his eyes.