When He began His ministry, Jesus Himself was about thirty years of age, being, as was supposed, the son of Joseph, the son of Eli,Luke 3:23(NASB)
It appears that His baptism in the Jordan was a particular milestone in Christ's life, which divided His three and a half year ministry from His pre-ministerial period. It was while Jesus was praying at His baptism that the voice of God was heard authenticating Him as "My beloved Son, in Who I am well pleased," while the Spirit of God descended upon Him in bodily form - like a Dove.
Luke includes Christ's genealogy at this point as a special marker showing the sovereign hand of God touching Christ's human lineage, which he traced back through David the king and Abraham the patriarch, through Noah, Enoch, Seth, and Adam.
It was following His unique baptism that we read: "When He began His ministry, Jesus Himself was about thirty years of age, being, as was supposed, the son of Joseph, (the husband of Mary) the son of Eli..." and thus, Luke recorded Christ's entire earthly lineage back to Adam, who was identified in Genesis as "the son of God."
While Matthew brings his genealogy through the official royal line of king David and king Solomon to Mary's husband, Joseph, who became the legitimate step-father of Jesus, Luke makes it clear that Joseph was presumed to be the father of Jesus, even though he traced Christ's lineage back through his mother, Mary, to king David's other son - Nathan.
In this distinctive manner, the Gospel of Luke prepares the reader for the hypostatic union of a holy God with perfect Man in the Person of Jesus Christ - the beloved Son of God and true Son of Man: "And Jesus was about 30 years of age when He began His ministry."
Throughout Scripture, we see that thirty was an important age for men to begin an office or ministry. It was at the age of thirty that Levitical priests began their priestly service. Joseph was made prime minister of Egypt at 30, while David became king of Israel at the same age.
In this verse, we read that the Lord Jesus Himself "was about thirty years of age when He began His ministry," which shows the critical importance God places on sound preparation and serious training before a man is equipped for an important ministry.
There are those that suggest that the phrase 'about thirty years of age' is more accurately translated 'exactly thirty years of age'. But whichever is correct, we discover that like the Levitical priests, David the king, and others that God has used mightily, Jesus had to go through many years of preparation and training before He was ready to fulfil the ministry for which He had been appointed.
May we be ready and willing to wait as long as it takes for God to prepare us for the work He has given us to do. Let us remember that there are no short-cuts to spiritual growth. Strong, secure, spiritual maturity is a gradual process which progresses from day to day, month to month, and year to year. It is a process that starts at salvation, continues through life, and at His appointed time will be used by God for His eternal glory.
May we grow in the grace and in a knowledge of our Lord and Saviour Jesus Christ as He prepares and equips us for the work that He has for us to do. To Him be the glory, both now and to the day of eternity, amen.
Heavenly Father, what an important lesson to learn that the Lord Jesus Himself was required to wait until He was about 30 years of age before He began the work that You prepared for Him to do. I pray that I may be willing to learn the lessons You would teach me and to wait for Your perfect timing in my life. Give me patience and a heart that is obedient to You. In Jesus' name I pray, AMEN.