'Acquainted' in the Bible

“The heart is deceitful above all thingsAnd it is extremely sick;Who can understand it fully and know its secret motives?

I will give them a heart to know Me, [understanding fully] that I am the Lord; and they will be My people, and I will be their God, for they will return to Me with their whole heart.

And each man will no longer teach his neighbor and his brother, saying, ‘Know the Lord,’ for they will all know Me [through personal experience], from the least of them to the greatest,” says the Lord. “For I will forgive their wickedness, and I will no longer remember their sin.”