The messiah in Isaiah 53:10 is said to offer his soul in restitution for Israel. As a reward, his days are prolonged and he is given children:
And the Lord wished to crush him, He made him ill; if his soul makes itself restitution, he shall see children, he shall prolong his days, and God's purpose shall prosper in his hand.*
The messiah's children are observant because we are told "God's purpose shall prosper in his hand".
Are the children born to the messiah literal or figurative?
The subject of the messiah from a Jewish perspective is complicated by the fact that in Judaism there are two, complementary messiahs.
THE VIEW OF JESUS CHRIST
Some Jews regard Jesus Christ as the first in rank and appearance of the Dual Messiahs. There is no record Jesus married or had literal children. However, the Gospels do attest to the positive place of children in the messianic kingdom.
In Matthew 19:14 Jesus said, "Suffer little children, and forbid them not, to come unto me: for of such is the kingdom of heaven".
In Matthew 19:29 Jesus said, "And every one that hath forsaken houses, or brethren, or sisters, or father, or mother, or wife, or children, or lands, for my name's sake, shall receive an hundredfold, and shall inherit everlasting life".
Jesus spoke of the children as the extended family of the household of faith.
THE VIEW OF THE OTHER MESSIAH
Because there are Dual Messiahs, messianic prophecies often have dual applications. Thus the figurative children of Jesus Christ could be paralleled by either the figurative or literal children of the other messiah.
The language of Isaiah 53:10 supports a practical application to the other messiah rather than Jesus Christ. This passage refers to a messiah whose days are prolonged after he suffers from personal illness.** There is no evidence Jesus ever suffered a disease.
THE REWARD OF RESTITUTION
Prolonged life and children are a reward to the messiah for offering his soul as restitution for Israel. Restitution is the act of restoring Israel from damage caused to it. Rome is responsible for destroying national Israel. Nero Caesar set in motion this process when he dispatched forces to quell a revolt in Judea in 67 C.E. Rome destroyed the Jewish Temple in 70 C.E. and in subsequent years exiled Jews from the Holy Land.
The Antichrist (the reborn Nero) in Revelation 13:1 arises with the power of Rome to restore national Judaism, which is described as the image (or vision) of the beast.
In gematria, 666 (Revelation 13:18) is the numerical value of "NERON KESAR", the Greek transliteration of Nero Caesar. "Neron Kesar" was the term used in the eastern portion of the Roman Empire as found on coinage from the period.
Nero is portrayed as both destroyed and savior; the Antichrist transformed from a negative figure to a positive one through a divine mystery. The pagan historian Suetonius cites contemporary predictions Nero would reign over (a presumably restored) Jerusalem:
"Astrologers had predicted to Nero that he would one day be repudiated, which was the occasion of that well known saying of his: 'A humble art affords us daily bread,' doubtless uttered to justify him in practising the art of lyre-playing, as an amusement while emperor, but a necessity for a private citizen. Some of them, however, had promised him the rule of the East, when he was cast off, a few expressly naming the sovereignty of Jerusalem, . . ." -- Ch. 40
Prolonged life and children are a reward to the messiah for offering his soul as restitution for Israel. The reborn Nero must first rebuild the Jewish Temple and restore national Israel before the inauguration of any messianic dynasty.
* Judaica Press Version.
** "Jehovah hath delighted to bruise him, He hath made him sick, . . ." (Young's Literal Translation). See also English Standard Version.