Shaikh Ibn Bāz, may Allāh have mercy on him, said:
It is upon you to accept evidence, not [go looking for] allowances [from other scholars or schools of thought]. One of the Salaf [our righteous predecessors in Islām] said, “Whoever goes looking for allowances will end up becoming a zindīq [a hypocrite—someone pretending to be a Muslim while he’s actually a disbeliever].
Every school of [jurisprudential] thought has some mistakes; some mistakes [came about] from those who followed [that school of thought], or [some came] from the imām [himself] to whom [the school of thought] is ascribed, that he made a mistake concerning some narrations [or] that some narrations [from the Prophet ﷺ] had been unknown to him. So a student of [Islāmic] knowledge should not go hunting for allowances [among the opinions of scholars].
Then if the issue were one about which [scholars] differ—it is not an issue [where scholars] unanimously agree—there are treatises [to be found on the issue] from among the people of knowledge; a student of knowledge [will] search for evidence and look to see [which] of the two sayings is closer to or stronger in its evidence and then take [an opinion] based on what the evidence supports, not [based] on looking out for allowances.