What does God mean when He says, "Not by might, nor by power, but by my Spirit" (Zechariah 4:6)?

TL;DR:

Through the prophet Zechariah, God encouraged the Israelites by assuring them His Spirit would accomplish the rebuilding of the temple, not their own power. Similarly, believers today have the indwelling Holy Spirit that assures us we can accomplish God’s will.

what does the bible say?

Zechariah 4:6 was God’s encouragement to the Israelites who had returned from Babylonian exile to rebuild the temple in Jerusalem. While rebuilding, the people faced obstacles. God gave Zechariah, a prophet and priest of Israel, multiple visions to show them His will would be accomplished despite those obstacles. In Zechariah’s fifth vision, he saw a gold lampstand with a bowl and seven lamps on top of it and two olive trees by it, which provided the oil needed to light the lamps (Zechariah 4:1–3). As in many other Old Testament passages (Isaiah 61:1–3; 1 Samuel 16:13), oil symbolizes the power of the Holy Spirit. The oil supply in Zechariah's vision was symbolic of the Holy Spirit's steady supply of power that would help Zerubbabel and the Israelites to complete the rebuilding of the temple, represented in the vision as the large lampstand. The lamps in the prophecy symbolized how God's people were supposed to shine as a light in the world to glorify God. The symbolism of light showing the truth to others is seen throughout the Bible (Isaiah 42:6; 49:6; Matthew 5:14). Zechariah 4:6 and many other passages in Scripture encourage God’s people to trust in His power (2 Corinthians 12:9–10; Ephesians 3:20; Philippians 4:13). With God’s promise, believers can, like the apostle Paul, confidently say, “I can do all things through him who strengthens me” (Philippians 4:13).

from the old testament

In Zechariah 4:6, God gives the prophet these words: “Then he said to me, ‘This is the word of the LORD to Zerubbabel: Not by might, nor by power, but by my Spirit, says the LORD of hosts.’” Throughout the time of rebuilding, the Israelites faced opposition that had even stopped construction. Through Zechariah, God assured them of success, not by their own might or power, but by the power of the Spirit of God.
Proverbs 21:31, like many Bible passages, reinforces the Lord’s sovereignty in accomplishing His will: “The horse is made ready for the day of battle, but the victory belongs to the LORD.” God cannot fail, and when we lean on and trust Him, neither can we.

from the new testament

In Romans 8, after writing about how God assures us of salvation, Paul says in verse 31, “What then shall we say to these things? If God is for us, who can be against us?” God is sovereign, and nothing can defeat His plan for us. Just as Zechariah’s assurance encouraged Zerubbabel to continue despite obstacles, Christians today can be assured that God will accomplish His plan and purpose for our lives.
In John 14:16, Jesus assures His disciples, “And I will ask the Father, and he will give you another Helper, to be with you forever.” When we accept Jesus as Savior, we receive the indwelling Holy Spirit, who provides us with strength we do not otherwise possess.
In 2 Corinthians 12:10, Paul writes something the world might think strange: "For the sake of Christ, then, I am content with weaknesses, insults, hardships, persecutions, and calamities. For when I am weak, then I am strong.” Paul doesn’t bemoan his frailty or circumstances because he knows the Holy Spirit will work through him to accomplish God’s purposes.

implications for today

Watch any bodybuilding competition, and you’ll see seemingly “impossible” feats of strength. During competitions, the weightlifters pose, and the audience gapes at the size of their muscles. When they lift 700 pounds (or more), we marvel at their strength and may think, “I could never do that!” (In most cases, that thought is true!) As a believer, have you ever thought the same about doing God’s will? Maybe you’ve seen others witness to complete strangers and thought, “I could never do that!” And maybe, like the audience who sees the bodybuilder lift 700 pounds, you’re correct—at least about your own strength. None of us has the power on our own to do what God has called us to do through Scripture. But we can accomplish His will, nonetheless, because He provides us with the strength we need through the Holy Spirit. God promised the Israelites He would accomplish His plan through His Spirit (Zechariah 4:6). God promises the same to us through the indwelling Holy Spirit, which He provides when we are saved (Romans 8:9; Ephesians 1:13–14). Through the Spirit, we can carry out more than we ever imagined. With God’s promise, believers can confidently say, like the apostle Paul, “I can do all things through him who strengthens me” (Philippians 4:13).

understand

God's work is accomplished by the Holy Spirit, not human strength.
The Holy Spirit empowers believers to fulfill God's purposes.
God promises to provide the strength needed for His work.

reflect

How do you rely on your own strength when facing challenges, and how can you learn to trust more fully in the Holy Spirit's power?
Are there areas in your life where you feel God's calling but doubt your ability to carry it out? How can you shift your perspective to rely on God's strength, rather than your own?
How have you experienced the Holy Spirit empowering you to accomplish things beyond your own abilities? How can you invite the Spirit to work through you more fully?

engage

How can we support and encourage other believers in recognizing and depending on the Holy Spirit's strength in our lives?
What are some practical ways we can encourage others to trust in God's Spirit when facing difficulties or pursuing God's will?
How do you think the promise of God's Spirit working through us can change our approach to ministry or serving others?