The scriptural warrant for frankincense is specific rather than general. Exodus 30 gives a formula for the sacred incense of the tabernacle and restricts it absolutely: it is to be compounded of stacte, onycha, galbanum and pure frankincense, and anyone who makes it for personal use is to be cut off from the people. Leviticus 2 requires frankincense on the grain offering. This is not incense as atmosphere; it is a regulated cultic substance.
The gifts of the Magi in Matthew 2 are gold, frankincense and myrrh. The text says nothing about three men, gives no names, and offers no interpretation of the gifts. The count of three is inferred from the count of the gifts, the names Caspar, Melchior and Balthasar first appear in Western sources several centuries later, and the reading of frankincense as signifying divinity and myrrh as signifying burial is patristic commentary rather than anything in the passage.
The trade itself is the largest fact here. The overland incense route ran up the western side of Arabia to the Mediterranean, and the cities that grew along it were built on this resin and on myrrh. Pliny the Elder complains in the Natural History about the sums draining east to pay for aromatics, and gives an account of the Arabian groves and the guarded harvest that is part observation and part traveller's tale. His irritation is good evidence of the scale.
The consumption was enormous. Herodotus records the annual frankincense tribute owed to the Persian king, and the caravan cities of the route (Petra, Palmyra, Shabwa, Timna), existed on the tolls levied on it. The collapse of that trade in late antiquity is among the causes usually given for the decline of southern Arabia's urban civilisation.