Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you: for every one that asketh receiveth; and he that seeketh findeth; and to him that knocketh it shall be opened.
Luke 11:7-8
The door is *always* locked only on the inside. Open it, and bid enter whom you would. They will come, whom you invite.
But beware: it works the same way for the demons as for the Holy Ones.
When you summon any of them – by prayer, or by invocation, or by a spell or enchantment, or by a curse – they do come, and enter in. But they generally come like thieves in the night [Revelation 16:15], so you might not usually notice their ingress at first, but rather only later as you see things missing from you, or from your life. The demons rob you of good things, while the angels remove the bad. NB: either sort of removal is likely to hurt. They are surgeries, either to repair or only to wound. Healing involves wounding; and any such procedure is going to damage the very tissues of your body – or, at the very least, to disrupt their normal operations, to which you had grown accustomed.
None who might enter your portals are tame; none behave obediently. All of them are wild. Any of them are apt to answer your prayers in the affirmative, but in some way horribly painful or costly to you, or at the very least unexpected.
The angels come to feed you; their adversaries come to feed on you.
Be careful what you ask for then, and of whom; be wary whom you admit.
Be sure to knock on the door that opens toward the Lady.
The Orthosphere 
Well said.
“The angels come to feed you; their adversaries come to feed on you.”
That’s a great line and so true. Unfortunately, the adversaries are gorging themselves at the moment.
Almost everyone’s doors are wide open these days. That is one of the great achievements of the Enemy in the last century: he has convinced billions of people that he is not real, and that evil is a matter only of personal preference. So, everyone has opened the castle gates.