Psalm 51:10-12 NIV
Create in me a pure heart, O God, and renew a steadfast spirit within me.  Do not cast me from your presence or take your Holy Spirit from me.  Restore to me the joy of your salvation and grant me a willing spirit, to sustain me.
In the Old Testament, God gave his Spirit to particular people and particular times for particular jobs. To have God send his Spirit upon you was a sign of his approval, backing and presence. The wonder of the New Testament is that he bestows his Spirit on all his followers, including you. You have God’s approval and backing! He is with you!
Spirit, work in me today so that I might live up to my Father’s estimation of me.