The witnessing and sealing Spirit.

Rom. 8:14,16; Eph. 1:13,14. 

Why should the children of a King
Go mourning all their days?
Great Comforter! descend and bring
Some tokens of thy grace.

Dost thou not dwell in all the saints,
And seal the heirs of heav'n?
When wilt thou banish my complaints,
And show my sins forgiv'n?

Assure my conscience of her part
In the Redeemer's blood
And bear thy witness with my heart,
That I am born of God.

Thou art the earnest of his love,
The pledge of joys to come;
And thy soft wings, celestial Dove,
Will safe convey me home.