The disciples said to Jesus, "Tell us what Heaven's kingdom is like." He said to them, It's like a mustard seed, the smallest of all seeds, but when it falls on prepared soil, it produces a large plant and becomes a shelter for birds of the sky. (20Thomas)

The reign of God is less a place and more a process. Rather than a city, a garden, or some similar destination, heaven is a state of becoming.

The reign of God is remarkable for its miniscule beginning. Yet the tiny seed can grow quickly and in one season become a considerable bush.

A state of becoming what? Explicitly, a place of shelter for the vulnerable. Implicitly, a source of many more sharp and spicy seeds.

The synoptic parallels are Mark 4:30-32 and Matthew 13:31-42.

Above is the cross of St. Thomas or sometimes called the Persian Cross.