'Everything' in the Bible
If we [freely] admit that we have sinned and confess our sins, He is faithful and just [true to His own nature and promises], and will forgive our sins and cleanse us continually from all unrighteousness [our wrongdoing, everything not in conformity with His will and purpose].
As for you, the anointing [the special gift, the preparation] which you received from Him remains [permanently] in you, and you have no need for anyone to teach you. But just as His anointing teaches you [giving you insight through the presence of the Holy Spirit] about all things, and is true and is not a lie, and just as His anointing has taught you, you must remain in Him [being rooted in Him, knit to Him].
whenever our heart convicts us [in guilt]; for God is greater than our heart and He knows all things [nothing is hidden from Him because we are in His hands].
Little children (believers, dear ones), guard yourselves from idols—[false teachings, moral compromises, and anything that would take God’s place in your heart].