Although it is not my intention to offend anyone, however, there is NO doubt in my mind that (over 27 years ago now) an invisible "Presence" (quite literally) came into my life and immediately began changing me from the inside out.  And since I had just confessed (to God) my desperate need for salvation, and asked the Lord Jesus to save me and enter into my life, I have NO doubt that it was He and His Spirit who did it, since He is the Lord, and (together with the Father) the Creator of everything  -- including those who Hate and Reject Him.  

Psalm 145:17-20; John 14:22-23; Revelation 3:20; Col. 1:15-18; Hebrews 1:1-14; Rom. 10:13

See also: Our Greatest Enemy