English poetry is based on rhyming words like, "I shot a hippopotamus with bullets made out of platium, but when they hit his tough hide, he just flatten them." (I didn't say it was good poetry.) Hebraic poetry (Psalms, Proverbs, Song of Solomon, Ecclesiastes, Job, etc.) is entirely different. It is based, not on rhyming words, but on parallel statements, rhythm, and meter . Unfortunately, when it is translated into English, the rhythm and meter features are destroyed because the number of syllables may change, but the unique parallelism survives. Synonymous poetry is when two parallel statements in Hebrew say the same thing but in different words, for example, "The Lord is my shepherd" & "I shall not want" are the same thought but in different words. If the Lord is truly my shepherd, I'll have everything I need; not necessarily everything I want, but everything I need. Look at something like Ps 79:4 and notice the parallelism. "We have become a reproach to our neighbors" & "A scoffing and derision to those around us." Sometimes the two parallel statements are opposite sides of the same thought, and this is known as anthetical poetry. A classic example would Proverbs 1:15, "My son, do not walk in the way with them" and "Keep your feet from their path."