سنن النسائي

It was narrated from Hudhaifah that: He saw a man praying (And his bowing and prostration) were lacking. Hudhaifah said to him: 'For how long have you been praying like this?' He said: "For forty years.' He said: 'You have not been praying for forty years and if you die praying like this, you will have died following a path other than the path of Muhammad (ﷺ). Then he said: 'It is possible for a man to pray briefly, but still do it properly."