honest to God

Short definition from Wiktionary

Adjective

1. 1
   Alternative form of honest-to-God.
2. 2
   real, true, actual, genuine, bona fide

Adverb

1. 1
   Honest; truly, really; used to emphasize that a statement is true.
2. 2
   Truly, really.
3. 3
   Alternative form of honest to God.