At the beginning of thy supplications the commandment came forth, and I am come to shew thee; for thou art greatly beloved: therefore understand the matter, and consider the vision.
At the beginning of thy supplications the commandment came forth. The promulgation of the divine decree was made in heaven to the angels as soon as Daniel began to pray.
Came forth - from the divine throne; so Daniel 9:22, "I am now come forth."
For thou art greatly beloved - literally, a man of desires (cf. Ezekiel 23:6; Ezekiel 23:12); the object of God's delight. As the Apocalyptic prophet of the New Testament, John was "the disciple whom Jesus loved." So the Apocalyptic prophet of the Old Testament was "greatly beloved" of God.
Understand the matter, and consider the vision - the further revelation as to Messiah in connection with Jeremiah's prophecy of 70 years of the captivity. The charge to "understand" is the same as in Matthew 24:15, where Rome primarily, and Antichrist ultimately, is referred to (cf. note, Daniel 9:27, below).