父 is an ideograph: a hand gripping a stone axe or staff, the working tool of the one who heads the household. The oracle-bone form draws a raised hand closed around a vertical implement, the slanting strokes above it the blade or the haft. The father is identified by what he holds, the tool that clears the field, splits the wood, and enforces the household order.

The Shuōwén Jiězì reads 父 as 矩也，家长率教者，从又举杖: a measure or rule, the head of the family who leads and instructs, drawn from 又 (a hand) raising a staff. The raised staff carries both senses at once, the labor of the provider and the authority of the disciplinarian. By the seal script the gripping hand had flattened into the four crossing strokes of the modern glyph, but the closed-fist shape still reads in the two inner strokes.

父 became its own radical and sits as the top element in the everyday words for father: 爸 bà (the colloquial 父 over the phonetic 巴), 爷 yé (grandfather), and 爹 diē (dad, dialectal and warm). Each one stacks the axe-holding figure above a sound component, so the father stands literally at the head of his own characters.

The character splits a tone in older usage. Read fù it means father and male elder; read fǔ it was an honorific suffix for a respected man, as in 渔父 yúfǔ, the old fisherman of the Chuci. Modern Mandarin keeps fù as the living reading.

父 reaches past the household to mark the whole parent-and-above generation. 祖父 zǔfù is the paternal grandfather, 父辈 fùbèi the fathers' generation as a class, 师父 shīfu the master who teaches a craft as a father teaches a son. In each the axe-holder stands for seniority and the duty of instruction, the same 家长率教者 that the Shuōwén named.

The word also climbs to the figurative. 国父 guófù, father of the nation, is the title given to a founding statesman; 父老 fùlǎo, the fathers and elders, addresses the senior men of a place as a body. Calling a man 父 is the strongest claim of respect the kinship system can make outside one's own blood.

See a weathered hand closing around the worn haft of a stone axe, knuckles raised, the blade catching the light. That fist is 父. The father is the one who holds the tool, the hand that splits the firewood and rules the household by the same grip.

The four strokes carry it: the two slanting marks above are the lifted blade, the crossed strokes below the fist that holds it. Once you see the hand and the axe, the modern shape stops being abstract and becomes a gesture frozen mid-swing.

Now stack the figure upward. Put it over 巴 and you get 爸 bà, dad. Put it over the grandfather's word and you get 爷 yé. Put it beside the master's 师 and you get 师父. The axe-holder rises to the top of every word for the men who lead and teach, exactly where the Shuōwén placed him: 家长率教者, the head of the family who leads and instructs.