Exodus 3:12 (KJV) says: "And he said, Certainly I will be with thee; and this shall be a token unto thee, that I have sent thee: When thou hast brought forth the people out of Egypt, ye shall serve God upon this mountain."

This verse is part of the conversation between Moses and God at the burning bush. In this pivotal moment, God is calling Moses to lead the Israelites out of Egyptian bondage. This verse is rich with themes of God's presence, guidance, and faithfulness.

The first part of the verse, "Certainly I will be with thee," speaks to the omnipresence of God. It reassures Moses that he will not be embarking on this monumental task alone. This promise of God's presence is echoed throughout the Bible, giving comfort and courage to believers in times of trial and decision. It also speaks to the nature of God as a faithful and constant companion to those who follow Him.

The second part of the verse, "and this shall be a token unto thee, that I have sent thee," serves as a sign or confirmation of God's calling and commissioning of Moses. Throughout the Bible, God often provides signs to His chosen leaders as a way of affirming His plan and purpose for their lives. In this instance, God is assuring Moses that he is indeed the chosen vessel through whom God will work to deliver the Israelites.

The final part of the verse, "When thou hast brought forth the people out of Egypt, ye shall serve God upon this mountain," points to the future fulfillment of God's plan. It sets the stage for the larger narrative of the Israelites' exodus from Egypt, their journey to the Promised Land, and the establishment of their covenant with God. It also signifies the importance of Mount Horeb (also known as Mount Sinai) as the place where God will reveal Himself to the Israelites and give them the law.

In a broader context, this verse speaks to the themes of divine calling and obedience. Moses initially hesitates and questions God's plan, but ultimately he submits to God's will and becomes an example of faith and obedience. This narrative of Moses' calling and reluctant acceptance serves as a model for believers who may also question or doubt their abilities to fulfill God's will.

Symbolically, the burning bush itself is a powerful image of God's presence and holiness. The fact that the bush is on fire but not consumed by the flames demonstrates the awe-inspiring nature of God and His ability to work through the ordinary and mundane. The burning bush also represents the divine encounter and commissioning that Moses experiences, marking a turning point in his life and in the history of the Israelites.

Overall, Exodus 3:12 is a pivotal verse in the biblical narrative, rich with themes of God's presence, guidance, faithfulness, divine calling, and obedience. It sets the stage for the epic story of the Israelites' exodus and serves as a timeless example of God's providence and sovereignty.