Romans 1:21
because though they knew [there was] a God, they glorified him not as God, nor gave him thanks, but became triflers in their disputations, and their stupid heart was darkened.
Romans 1:28-30
And since they thought not fit to hold the Deity in acknowledgment, God abandoned them to a reprobate mind, to practise deeds unbecoming;
2 Corinthians 6:15
and what concord of Christ with Belial? or what share hath he that believeth with an infidel?
John 8:55
yet have ye not known him; but I know him: and if I should say, that I know him not, I should be like you, a liar: but I know him, and observe his word.
John 16:3
And these things will they do unto you, because they have not known the Father, nor me.
John 17:3
and this is eternal life, that they should know thee the only true God, and him whom thou hast sent, Jesus, the Messiah.