Matthew 6:11, “Give us this day our daily bread.”
What does this mean? “God gives daily bread without our prayer, even to all evil people, but we ask in this prayer that God cause us to recognize what our daily bread is and to receive it with thanksgiving” (SC, “The Lord’s Prayer,” 13; KW 357). What is our daily bread? Any basic need, such as food, clothing, shoes, jobs, good health, good government, good weather, livestock, etc.
God gives all of these without our asking, even to unbelievers, for He desires that they should live and turn from their wicked ways (Ezekiel 18:23). If you go to your local grocery store and purchase food, God has provided your daily bread. He does the same when He provides medicine, healthcare, healing (physical or mental), etc. All these and more He gives often without our asking.
Yet in this petition, as Luther says, we also pray to recognise what our basic needs are. So, if you have good health but lack a job, seek God in prayer for this need. If you have a job but are in poor health, pray for this need (and do not neglect seeing your doctor!). Whatever your basic need is, pray for it, for in this petition God promises to give us all we need to live. This does not mean He promises luxury or financial prosperity—though He can certainly choose to work that way—but simply exactly what we need to live in our given situation.
Kolb, Robert, Timothy J. Wengert, and Charles P. Arand. The Book of Concord: The Confessions of the Evangelical Lutheran Church. Minneapolis: Fortress Press, 2000.