Truly, truly, I tell you, whoever hears My word and believes Him who sent Me has eternal life and will not come under judgment. Indeed, he has crossed over from death to life. John 5:24 NIV
Christ reveals here the Truth of believing the words He speaks and the One who sent Him. The Father and Son are united in oneness. One must understand that to not come under judgement belief in the words of the Lord and belief in the Father and the Son are paramount. To one who asks that which they must do in order to not be judged, refer them to this scripture verse.
By not being judged one passes from death to life spiritually. This occurs while we still live within the mortal body, and we shall be with God in Spirit for eternity. The passing of the mortal body shall have no control over our eternity with the Father and the Son.