2 Samuel 19:7

Now therefore arise, go forth, and speak comfortably unto thy servants: for I swear by the Lord, if thou go not forth, there will not tarry one with thee this night: and that will be worse unto thee than all the evil that befell thee from thy youth until now.

Cross-references

Hosea 2:14 uses the exact same Hebrew idiom 'speak to her heart' for God alluring Israel. Joab uses it for David reconciling with his men.

Genesis 34:3 uses the same Hebrew idiom 'speak to the heart' (speak tenderly) as Joab urges David to do with his servants.