Psalm 15 opens with the questions:
Lord, who may abide in Your tabernacle?
Who may dwell in Your holy hill?
In other words who is the person close to God, intimate with Him.
The Psalm goes on to give the answer:
He who does not backbite with his tongue,
Nor does evil to his neighbor,
Nor does he take up a reproach against his friend;
4 In whose eyes a vile person is despised,
But he honors those who fear the Lord;
He who swears to his own hurt and does not change;
5 He who does not put out his money at usury,
Nor does he take a bribe against the innocent.
In other words, the person close to God is the person who treats people the way God does, the person who reflects His character.
Amos 3:3 says:
Can two walk together, unless they are agreed?
We walk with God, are close to Him when our lives “agree” with His, demonstrated by our actions reflecting His.
This statement of agreement brings intimacy.