Jesus says being a slave for Him is the most freeing thing you can do. A slave to anything else causes bondages. According to the Legacy Standard Bible every place where servant is used it is in the direction of being a slave.
Two things however to say: maybe slave should not be used every time but instead use servant some of the time because servant is more voluntary than slave. Also, servant is more halfway in-between slave and friend; Jesus calls his disciples and all believers friends. More from the aspect of surrender to Christ we are slaves. Not the aspect of Choice. If people were completely slaves to Christ, then they would never sin. True love deserves a choice. We are a complete slave to Christ in Heaven because in Heaven there is no sin.
If people knew how freeing it is to surrender to Christ like a slave, they would have asked Him, and he would have given them the truth that sets them free.
God as Perfect Father is important also because people need to feel blessed by God the Father. Jesus at age 12 was doing his Fathers Business also at the end of His life He gave up His Holy Ghost to God the Father. How God the Father is Greater than Jesus, yet they are one is a mystery.
Based on the following Scriptures
John 8:31-38
Matthew 25:22-23
John 15:14-17
Luke 2:41-52
Luke 23:46
