Satan works wherever he has been given ground through sin. The scriptures do not teach that we can claim the protection of the blood of Jesus for others. By claiming “the shelter of the blood”, in an assembly, the people are given a false security; they do not use discernment to prove all things and are vulnerable to the working of the powers of darkness.
“ … if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.” 1 John 1:7 “If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.” 1 John 1:9
“Having therefore, brethren, boldness to enter into the holiest by the blood of Jesus,” Hebrews 10:19
“And I heard a loud voice saying in heaven, Now is come salvation, and strength, and the kingdom of our God, and the power of his Christ: for the accuser of our brethren is cast down, which accused them before our God day and night. And they overcame him by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death.” Revelation 12:10-11