步 = suri [Jap] - bu4 [Chin]
法 = ashi [Jap] - fa3 [Chin]
The second ideogram - "法" - is common in older Chinese language texts, usually found in the context of an authoritative set of rules that cannot be improved upon. This term is used in both religious and secular texts. However, the ideogram - "步" - is the operative character.
The "步" ideogram is comprised of an upper and lower particle:
Upper Particle = 止 (zhi3) - originally - a three-toed bare-foot-print (the mark left by a "still" human foot)
Lower Particle = 𣥂 (ta4) - a foot in motion - stepping forward (or backward) via heel-toe, or toe-heel orientation
In other words, to "step", "pace", and to "measure" a specific "distance" between the two-feet when walking (or "stepping") forward, back, between both sides, and along the diagonals, etc.