4:9 known of God. Note that Paul places special emphasis on being “known of God.” God knew us before we knew Him!
4:9 beggarly elements. Before their conversion, the Galatians had been pagans (perhaps some had been Jews, as was true in most of the early churches). If pagans, they had been in bondage to evolutionary pantheistic polytheism, committed to many pagan rituals and sacrifices. If Jews, they had been in bondage to Jewish law and tradition, hoping to earn salvation by the impossible burden of obeying all the laws. No wonder Paul was impatient with their desire to give up liberty in Christ for renewed bondage.