Luther sits next to 3 phonetic neighbors — Luca, Luther, and Tucker are the closest matches by sound. Most share Luther's German-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"famous army, warrior people"
"dweller in the valley"
"oracle, mouth of brass"
"thankful, grateful"
"son of Harry, home ruler"
"from the coal settlement"
"crooked enclosure"
"brave bear, strong as a bear"
"speed, power (modern association)"
"little fire"
"tumult, noise"
"beloved youngest son"
"little fire, fiery one"
"servant of God"
"nobleman of the second rank"
"divine bear"
"the Lord is my God"
"God is salvation"
"god of war"
"luminous, shining"
"warrior, battle"
Similar sound: These names share phonetic patterns with Luther — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old High German origins, giving them the same cultural heritage as Luther.
Rhythm: Luther is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.