How are believers able to call God Abba, Father?

Les explains that the unsaved world cannot approach God as Heavenly Father, and any attempt without salvation accomplishes nothing. But believers can come right into the throne room and call Him Father. As Paul teaches, they come with all their petitions, not on their own merit, but because of the finished work of the cross. Because of salvation, believers are born ones, and God immediately sends the Spirit of His Son into their hearts. In response, through the leading and guiding of the Holy Spirit, they have every right to call Him Abba, Father. Les also notes Paul’s use of “wherefore” shows progressive revelation: believers are no longer servants or little children under tutors, but full-blown sons in full partnership with the Father.