Whoso denieth Guardian hath denied God;

The sacred and youthful branch, the guardian of the Cause of God as well as the Universal House of Justice, to be universally elected and established, are both under the care and protection of the Abhá Beauty, under the shelter and unerring guidance of His Holiness, the Exalted One (may my life be offered up for them both). Whatsoever they decide is of God. Whoso obeyeth him (Guardian) not, neither obeyeth them hath not obeyed God; whoso rebelleth against him (Guardian) and against them hath rebelled against God; whoso opposeth him (Guardian) hath opposed God; whoso contendeth with them hath contended with God; whoso disputeth with him (Guardian) hath disputed with God; whoso denieth him hath denied God; whoso disbelieveth in him hath disbelieved in God; whoso deviateth, separateth himself and turneth aside from him hath in truth deviated, separated himself and turned aside from God. May the wrath, the fierce indignation, the vengeance of God rest upon him! The mighty stronghold shall remain impregnable and safe through obedience to him who is the guardian of the Cause of God.

(The Will & Testament of Abdu'l Baha)