The repetitions are emphatic; expressive of anxious love.
Son of my vows - Like Samuel, and Samson, the child often asked for in prayer, the prayer ratified by a vow of dedication. The name Lemuel (literally “for God,” consecrated to Him) may be the expression of that dedication; and the warning against indulging in wine Proverbs 31:4 shows that it had something of the Nazarite or Rechabite idea in it.