The phrase 'in the streets and synagogues' in Matthew 6:2, 5, and Luke 8:26-27, refers to a representative rite amongst the Jews to teach in streets. In the prophets, wherever streets are mentioned, they either signify truths or falsities.

In Revelation 22:2, the streets represent every facet of truth that leads to goodness, or in other words, every facet of faith that leads to love and charity. (Arcana Coelestia 2336[2])

In Luke 14:21, this going to the streets signifies to seek everywhere for some genuine truths. (Arcana Coelestia 2336[4])

(References: Arcana Coelestia 2336)