Exodus 4:27
And the LORD said to Aaron, Go into the wilderness to meet Moses. And he went, and met him in the mount of God, and kissed him. And the LORD said to Aaron, Go into the wilderness to meet Moses. And he went, and met him in the mount of God, and kissed him.
The Lord directed Aaron to go out into the wilderness to meet Moses. In obedience Aaron went and met him at the mount of God. The place where they met and spoke together was near Horeb. Their meeting was the reunion of brothers after years of separation.
They greeted one another with a kiss. God had chosen Aaron to assist and work with Moses in the deliverance of Israel. Moses then told Aaron all the words and message of God and the signs entrusted to him for Israel. Aaron had been instructed to listen to Moses, who would tell him God's words and the part he was to act in the deliverance.