The writer did not list Shecaniah among those who had married foreign wives (cf. Ezra 10:18-44). He appears to have been another faithful Jew like Ezra. The present situation distressed him. He too, though faithful, identified with the unfaithful. [source][source][source]
Shecaniah proposed divorce, not separation. The Hebrew word translated "put away" ( Ezra 10:3) is the same as the one translated "leaves" in Deuteronomy 24:2 where divorce is in view. "According to the law" ( Ezra 10:3) probably refers to the law specifying the procedure for divorce in Deuteronomy 24 (i.e, with a certificate of divorce). In Deuteronomy 24:1 God permitted divorce for "some indecency" in the wife. Perhaps Ezra viewed these pagan women"s beliefs and practices as indecent. [1] In the ancient Near East, mothers received custody of their children when there was a divorce (cf. Genesis 21:14). However, in Greece they went with their fathers. [2][source]
"Foreign women were married contrary to the law of God. The marriages were illegal from the outset. The sending away of the women is to guard the exiles against the continuation of an illegal act. With their foreign wives they lived in sin. It is thus clear from Ezra 10:4 that there is a strong legal background against which Shecaniah has formulated his proposal. The dividing line between the permissible and impermissible is strongly emphasized. Even the children born from the illegal marriages must be sent away. This proposal is harsh in the light of modern Christian conceptions. Why should innocent children be punished? We must remember that the religious influence of the mothers on their children was regarded as the stumbling block. To keep the religion of the Lord pure was the one and only aim of Ezra and the returned exiles. As a small minority group, the repatriates lived in the Holy Land among a large population of influential people who were followers of various polytheistic religions. Against such larger numbers they had to defend themselves and their religious identity. Thus the drastic measures are understandable." [1][source]
Even today, some Jewish leaders view intermarriage with non-Jews as the major threat to the continuation of Judaism. [source][source][source]
"Therefore, the greatest danger to Jewish survival outside Israel today is not anti-Semitism but assimilation, epitomized by the threat of intermarriage ... [4] is a direct threat to Judaism, for without Jews Judaism cannot exist." [5][source]
". . . the situation described in Ezra 9 , 10 was a classic example of one in which the lesser of two evils had to be chosen." [6][source]