I hope, this will be not the next Question of the Day, but sometimes you have the value not in a binary column but in a VARCHAR (e.g. because you imported it from an CSV).
In this case:
SELECT CAST(0x00006B61 AS INT) -- value is already a binary
, CAST(CONVERT(BINARY(4), '0x00006B61', 1) AS INT) -- value is a varchar with leading 0x followed by a hex code
, CAST(CONVERT(BINARY(4), '00006B61', 2) AS INT) -- value is a varchar without leading 0x (only the hex code)
will do the job...
God is real, unless declared integer.