A.T. Robertson Commentary Mark 11:23

"Verily I say unto you, Whosoever shall say unto this mountain, Be thou taken up and cast into the sea; and shall not doubt in his heart, but shall believe that what he saith cometh to pass; he shall have it." — Mark 11:23 (ASV)

Shall not doubt in his heart (μη διακριθη εν τη καρδια αυτου). First aorist passive subjunctive with ος αν. The verb means a divided judgment (δια from δυο, two, and κρινω, to judge). Wavering doubt. Not a single act of doubt (διακριθη), but continued faith (πιστευη).

Cometh to pass (γινετα). Futuristic present middle indicative.