A servant of God is part of God’s household and he works to serve his master. The nation of Israel were considered servants of God. Hebrews 3:5, “Moses was faithful as a servant in all God’s household.”
God gave the Law to Israel to teach them their need for a savior. Galatians 3:24 (NIV), “So the law was our guardian until Christ came that we might be justified by faith.” Those Jews who received the Law’s instruction and developed tender, reverent hearts were prepared to recognize Jesus as their savior.
During His first advent, Jesus explained to His disciples that they were living in a transition period. Faithful servants in the Law were invited to a closer relationship with God as friends of God. John 15:15 (NIV), “I no longer call you servants, because a servant does not know his master’s business. Instead, I have called you friends, for everything that I learned from my Father I have made known to you.”
After Jesus completed His sacrifice as our ransom, the invitation to sonship was opened. We are adopted as sons through “a new and living way which He inaugurated for us through the veil, that is, His flesh,” Hebrews 10:20 (NASB). “For ye are all the children of God by faith in Christ Jesus,” Galatians 3:26-28.
If we are faithful sons of God, then we become heirs with Christ. "And if children, then heirs; heirs of God, and joint-heirs with Christ, if so be that we suffer with him, that we may be also glorified together." Romans 8:17. In the resurrection, we will receive our blessed inheritance. “Beloved, now we are children of God…when He appears, we will be like Him, because we will see Him just as He is.” 1 John 3:2. “What no eye has seen, nor ear heard, nor the heart of man imagined, what God has prepared for those who love him,” 1 Corinthians 2:9.
However, all sons of God also serve God. True Christians are both sons and servants of God. Jesus, Himself, came to serve. Mark 10:44-45 (NASV), “And whoever of you desires to be first shall be slave of all. For even the Son of Man did not come to be served, but to serve.” Therefore, let us remember “by love (to) serve one another,” Galatians 5:13.