The strength you want most may not be the strength you need most, because the weakness you feel may not be the real source of your weakness.

When we begin to feel weak or exhausted, it may be that we’re physically worn out — from work, from relationships, from parenting, from life. We all have days we could go to sleep early, and still sleep until noon — at least if it weren’t for, well, life.

Diet, exercise, and sleep all factor into our strength for any given day, but only incrementally compared to the spiritual resources we need. The strength we really need most from God today isn’t weighed in calories or defined by REM cycles, because the most important things he has called us to do today run deeper and higher than what we typically see and feel.

What Kind of Strength?

Seven words leapt off the page at me recently when reading the story of Saul’s conversion in Acts 9 — probably because I have felt especially weak in the stress of selling our house and moving our young family into a new home: “Saul increased all the more in strength” (Acts 9:22).

The risen Christ blinded Saul after confronting him on the Damascus road. Saul was so disoriented and awestruck that he refused to eat or drink for three days. He was physically depleted, to say the least. When Ananias laid hands on Saul to heal and anoint him, Luke says, “Immediately something like scales fell from his eyes, and he regained his sight. Then he rose and was baptized; and taking food, he was strengthened” (Acts 9:18–19). Food helped. He began to regain physical strength he lost without food and water.

But the word Luke uses for strength three verses later is different: “Saul increased all the more in strength, and confounded the Jews who lived in Damascus by proving that Jesus was the Christ” (Acts 9:22). Luke uses the Greek root of this “strength,” in various forms, 86 times in his Gospel and the book of Acts — and none of them are talking about food or sleep. We’re talking about power and ability, and very often the power and ability to do the supernatural — to understand and explain the word of God (Acts 18:24), to heal (Luke 9:1), to do good (Acts 10:38), or perform miracles (Acts 8:13), or witness to Jesus (Acts 1:8).

In fact, many of the texts refer, directly or indirectly, to what God himself can do (for instance, Luke 1:37; 5:17, 21; Acts 2:24), even when he chooses to do it through people like Saul. When Saul “increased all the more in strength,” God wasn’t refreshing his body to survive another day; he was filling him with power to do the impossible. That is the strength you and I need most today.

Stronger in God

So how do we live and serve and work in that kind of strength? Saul, who we also know as the apostle Paul, went on to write thirteen letters to churches, and used the same verb seven times in his writing. Each one uncovers an aspect of the real, genuine strength we need to do the spiritually impossible.

Strengthened in faith

No unbelief made him waver concerning the promise of God, but he grew strong in his faith as he gave glory to God, fully convinced that God was able to do what he had promised. (Romans 4:20–21)

The strength we need most doesn’t begin in our arms or legs or back, but somewhere deep in our soul. The fatigue we feel physically should remind us of how quickly our hearts are prone to wander and fail. Wisdom will ask God to strengthen faith far more often than it asks him to strengthen the body.

Strengthened by grace

You then, my child, be strengthened by the grace that is in Christ Jesus. (2 Timothy 2:1)

The strength we need most is not earned, achieved, or micromanaged. It is given as a gift, and to the undeserving. If you think you can schedule, diet, or even sleep your way to real strength, you will always lack the resources you need to glorify God. No, real strength knows that apart from him we can do nothing.

Strengthened with God’s strength

Finally, be strong in the Lord and in the strength of his might. (Ephesians 6:10)

When you experience real strength, it will not be because you finally tapped into your strength, but because you finally gave up relying on your own strength. Society may want you to believe you’re filled with unbounded potential to accomplish the impossible, but the key to achieving anything truly meaningful or lasting is realizing we will not achieve anything truly meaningful or lasting on our own. If you feel weak, you do not need more of you; you need more of God.

Strengthened against evil

Next verse: “Put on the whole armor of God, that you may be able to stand against the schemes of the devil. For we do not wrestle against flesh and blood, but . . . against the spiritual forces of evil in the heavenly places.” (Ephesians 6:11–12)

God fills us with his strength and issues us his armor for more than the eye can see. He is not simply preparing us to survive another day of work, or marriage, or family, or even ministry. He’s preparing us to defeat the devil, to stand in his strength against evil — the evil deceiving us from within and the evil attacking us from without. If you try to battle Satan and his demons on your own, burnout will be the least of your problems.

Strengthened to serve

I thank him who has given me strength, Christ Jesus our Lord, because he judged me faithful, appointing me to his service, though formerly I was a blasphemer, persecutor, and insolent opponent. (1 Timothy 1:12–13)

Negatively, God strengthens us against evil. Positively, God strengthens us to serve. The strength you need most today is not meant for you to keep for yourself, but to expend for the good of others. When God showers us with his grace and sends us his strength, he means for it to be spent in love on the needs and interests of people in our lives. When we use the strength we receive from God to serve others (and not ourselves) in Jesus’s name, he gets the glory (Matthew 5:16). We serve “by the strength that God supplies — in order that in everything God may be glorified through Jesus Christ” (1 Peter 4:11).

Strengthened to speak

The Lord stood by me and strengthened me, so that through me the message might be fully proclaimed and all the Gentiles might hear it. (2 Timothy 4:17)

We don’t only serve in God’s strength. He also strengthens us to say something about him. We don’t need strength merely to do the right thing — at home, at work, in our neighborhood — but to speak up about with courage and boldness about Jesus. When you ask God for the strength to do what he has called you to do today, remember your first and greatest calling: “Make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you” (Matthew 28:19–20).

Strengthened for Every Circumstance

I have learned in whatever situation I am to be content. I know how to be brought low, and I know how to abound. In any and every circumstance, I have learned the secret of facing plenty and hunger, abundance and need. I can do all things through him who strengthens me. (Philippians 4:11–13)

When Saul “increased all the more in strength” as a new believer and ambassador for Christ, God was strengthening and equipping him to face anything — hunger and plenty, need and abundance. It’s a reminder that we need this strength as much in blessing as we do in suffering, as much in success as we do in failure, as much in health as we do in sickness.

God strengthens us not only to defy evil, and serve others, and share boldly, but to be content in every circumstance — to experience a deep and confident joy in him regardless of our weaknesses and trials.