Believers have spirit of adoption as children of God and cry, "Abba! Father"!
Mark 14:35–36 (ASV 1901)
35And he went forward a little, and fell on the ground, and prayed that, if it were possible, the hour might pass away from him. 36And he said, Abba, Father, all things are possible unto thee; remove this cup from me: howbeit not what I will, but what thou wilt.
Romans 8:15 (ASV 1901)
15For ye received not the spirit of bondage again unto fear; but ye received the spirit of adoption, whereby we cry, Abba, Father.
Galatians 4:6 (ASV 1901)
6And because ye are sons, God sent forth the Spirit of his Son into our hearts, crying, Abba, Father.