Is a scholar who speaks with bid‘ah (innovation) or agrees with the people of bid‘ah in a specific innovation considered one of them?

A scholar is not considered an innovator, nor are they attributed to innovators if they agree with them on one issue. An example of this is someone who adopts the opinion of one Imam on a specific matter while following the school of thought of another Imam; it is not permissible to attribute him to the former. If a mujtahid scholar errs, he still receives a reward. And whoever rejects the truth because of an error made by its proponent is misguided, especially if the error was not, in fact, an error. Some people may wrongly judge those who disagree with them by declaring them disbelievers or misguided, and this is a very bad doctrine. And he who declares people disbelievers for any sin is misguided and opposes the Quran and Sunnah; indeed, he is worse than the Khawarij, who only declare the perpetrator of a major sin a disbeliever. Allah Almighty said: ﴿If you avoid the major sins which you are forbidden, We will remove from you your lesser sins and admit you to a noble entrance [into Paradise].﴾ And the Prophet, peace and blessings be upon him, said: "Whoever calls his brother an infidel—meaning, if it is not as he said—it will return to him."