Famous speech impediments

Moses - According to the Bible, Moses had a speech impediment. When God told Moses to free the Israelites (Jews) from slavery in Egypt, Moses replied, "But my Lord, never in my life have I been a man of eloquence, either before or since you have spoken to your servant. I am a slow speaker and not able to speak well" (Exodus 4:10). In Koran, 20:26-29 Moses said "Lord, open my breast, and do Thou ease for me my task, Unloose the knot upon my tongue, that they may understand my words." The analogy of a knot upon his tongue refers to his stuttering.