What does Exodus 4:27 mean?

Moses has survived an odd event which nearly cost him his life (Exodus 4:24–26). Now he returns to his mission (Exodus 3:10) which involves returning to Egypt (Exodus 4:19–23). The Lord had already noted that Aaron, Moses' brother, would meet him (Exodus 4:14). Some interpreters believe that the prior incident was a sidenote, and that Moses and Aaron met before Moses began his travels.

In either case, Scripture does not indicate how Aaron received this call from the Lord. In some way, he is told that he needs to meet Moses. The mountain in question is Sinai (Exodus 3:1; 18:5). This would be where God delivered His commandments to Israel (Exodus 19:1–3) and also the site of Aaron's greatest failure (Exodus 32:1–6).

The "kiss" depicted here refers to a sign of friendship and respect (Genesis 27:26; 33:4; Luke 22:48). This is probably given mention because of what it meant to Moses. We're not told how long it's been since he communicated with Aaron (Exodus 2:15). Nor are we told what the relationship was like. The fact that Aaron kisses Moses when they meet signifies a positive relationship right from the beginning. Moses seemed hesitant to take on this task (Exodus 4:13), so this friendly greeting would help ease his nerves.