Then the latter shall come into the realm of the king of the south but shall return to his own land.
This clause belongs to the former verse; as if he had said, Ptolemy shall return by a peaceful march after this hostile invasion of Syria. For he might have some fears lest his enemy should not be completely prostrated. But as he departed as conqueror, the angel announces his safe arrival in his own land.
Two great kingdoms rose from Alexander's remains: Egypt under Ptolemy and Syria under Seleucus, who became the mightier. Both pressed hard against Judah until they tried to bind themselves by marriage, iron and clay that would not hold together.
AI summary
Commenting on Daniel 11:5-20
So the king of the south shall come into his kingdom,.... Into his own kingdom, the kingdom of Egypt; or into the kingdom of Syria, the kingdom of Seleucus, and conquer great part of it, and ravage and spoil it: and shall return into his own land; the land of Egypt; he shall go and come with ease, and as he pleases, none to hinder...